Type.GetProperty Method

Definition

取得目前 Type 的特定屬性。Gets a specific property of the current Type.

Overloads

GetProperty(String)

搜尋具有指定名稱的公用屬性。Searches for the public property with the specified name.

GetProperty(String, BindingFlags)

使用指定的繫結條件約束搜尋指定的屬性。Searches for the specified property, using the specified binding constraints.

GetProperty(String, Type)

搜尋具有指定名稱和傳回類型的公用屬性。Searches for the public property with the specified name and return type.

GetProperty(String, Type[])

搜尋指定的公用屬性,其參數符合指定的引數類型。Searches for the specified public property whose parameters match the specified argument types.

GetProperty(String, Type, Type[])

搜尋指定的公用屬性,其參數符合指定的引數類型。Searches for the specified public property whose parameters match the specified argument types.

GetProperty(String, Type, Type[], ParameterModifier[])

搜尋指定的公用屬性,其參數符合指定的引數類型和修飾詞。Searches for the specified public property whose parameters match the specified argument types and modifiers.

GetProperty(String, BindingFlags, Binder, Type, Type[], ParameterModifier[])

使用指定的繫結條件約束搜尋指定的屬性,而該屬性的參數符合指定的引數類型和修飾詞。Searches for the specified property whose parameters match the specified argument types and modifiers, using the specified binding constraints.

GetProperty(String)

搜尋具有指定名稱的公用屬性。Searches for the public property with the specified name.

public:
 System::Reflection::PropertyInfo ^ GetProperty(System::String ^ name);
public:
 virtual System::Reflection::PropertyInfo ^ GetProperty(System::String ^ name);
public System.Reflection.PropertyInfo GetProperty (string name);
member this.GetProperty : string -> System.Reflection.PropertyInfo
abstract member GetProperty : string -> System.Reflection.PropertyInfo
override this.GetProperty : string -> System.Reflection.PropertyInfo
Public Function GetProperty (name As String) As PropertyInfo

Parameters

name
String

字串,包含要取得的公用屬性名稱。The string containing the name of the public property to get.

Returns

PropertyInfo

物件,代表具有指定之名稱的公用屬性 (如有找到),否則為 nullAn object representing the public property with the specified name, if found; otherwise, null.

Implements

Exceptions

找到一個以上具有指定名稱的屬性。More than one property is found with the specified name.

namenullname is null.

Examples

下列範例會抓取使用者定義類別的 Type 物件、抓取該類別的屬性,並顯示內容名稱。The following example retrieves the Type object of a user-defined class, retrieves a property of that class, and displays the property name.

using namespace System;
using namespace System::Reflection;
ref class MyClass
{
private:
   int myProperty;

public:

   property int MyProperty 
   {
      // Declare MyProperty.
      int get()
      {
         return myProperty;
      }

      void set( int value )
      {
         myProperty = value;
      }
   }
};

int main()
{
   try
   {
      // Get the Type object corresponding to MyClass.
      Type^ myType = MyClass::typeid;
      
      // Get the PropertyInfo object by passing the property name.
      PropertyInfo^ myPropInfo = myType->GetProperty( "MyProperty" );
      
      // Display the property name.
      Console::WriteLine( "The {0} property exists in MyClass.", myPropInfo->Name );
   }
   catch ( NullReferenceException^ e ) 
   {
      Console::WriteLine( "The property does not exist in MyClass. {0}", e->Message );
   }
}

using System;
using System.Reflection;

class MyClass
{
    private int myProperty;
    // Declare MyProperty.
    public int MyProperty
    {
        get
        {
            return myProperty;
        }
        set
        {
            myProperty=value;
        }
    }
}
public class MyTypeClass
{
    public static void Main(string[] args)
    {
        try
        {
            // Get the Type object corresponding to MyClass.
            Type myType=typeof(MyClass);
            // Get the PropertyInfo object by passing the property name.
            PropertyInfo myPropInfo = myType.GetProperty("MyProperty");
            // Display the property name.
            Console.WriteLine("The {0} property exists in MyClass.", myPropInfo.Name);
        }
        catch(NullReferenceException e)
        {
            Console.WriteLine("The property does not exist in MyClass." + e.Message);
        }
    }
}
Imports System.Reflection
Class MyClass1
    Private myProperty1 As Integer
    ' Declare MyProperty.

    Public Property MyProperty() As Integer
        Get
            Return myProperty1
        End Get
        Set(ByVal Value As Integer)
            myProperty1 = Value
        End Set
    End Property
End Class

Public Class MyTypeClass
    Public Shared Sub Main(ByVal args() As String)
        Try
            ' Get Type Object corresponding to MyClass.
            Dim myType As Type = GetType(MyClass1)
            ' Get PropertyInfo object by passing property name.
            Dim myPropInfo As PropertyInfo = myType.GetProperty("MyProperty")
            ' Display Name propety to console.
            Console.WriteLine("The {0} property exists in MyClass.", myPropInfo.Name)
        Catch e As NullReferenceException
            Console.WriteLine("The property does not exist in MyClass.", e.Message.ToString())
        End Try
    End Sub
End Class

就內部而言,此屬性在中繼資料中是由名稱 "Item" 所參考。Internally, this property is referred to in the metadata by the name "Item." 使用反映取得 PropertyInfo 的任何嘗試都必須指定此內部名稱,才能正確地傳回 PropertyInfo 屬性。Any attempt to get PropertyInfo using reflection must specify this internal name in order to correctly return the PropertyInfo property.

Remarks

name 的搜尋會區分大小寫。The search for name is case-sensitive. 搜尋包括公用靜態和公用實例屬性。The search includes public static and public instance properties.

如果屬性至少有一個公用存取子,則會將其視為公開給反映。A property is considered public to reflection if it has at least one accessor that is public. 否則,屬性會被視為私用,而且您必須|使用| BindingFlags.NonPublic BindingFlags.Instance BindingFlags.Static (在 Visual Basic 中,使用 Or來結合值)以取得它。Otherwise the property is considered private, and you must use BindingFlags.NonPublic | BindingFlags.Instance | BindingFlags.Static (in Visual Basic, combine the values using Or) to get it.

如果目前的 Type 代表結構化的泛型型別,這個方法會傳回 PropertyInfo,其中的型別參數是由適當的型別引數所取代。If the current Type represents a constructed generic type, this method returns the PropertyInfo with the type parameters replaced by the appropriate type arguments.

如果目前 Type 表示泛型型別或泛型方法定義中的類型參數,這個方法會搜尋類別條件約束的屬性。If the current Type represents a type parameter in the definition of a generic type or generic method, this method searches the properties of the class constraint.

發生 AmbiguousMatchException 的情況包括下列各項:Situations in which AmbiguousMatchException occurs include the following:

  • 類型包含兩個具有相同名稱但參數數目不同的索引屬性。A type contains two indexed properties that have the same name but different numbers of parameters. 若要解決不明確的問題,請使用指定參數類型之 GetProperty 方法的多載。To resolve the ambiguity, use an overload of the GetProperty method that specifies parameter types.

  • 衍生的型別會使用 new 修飾詞(在 Visual Basic 中Shadows)宣告屬性,以隱藏具有相同名稱的繼承屬性。A derived type declares a property that hides an inherited property with the same name, by using the new modifier (Shadows in Visual Basic). 若要解決不明確的問題,請使用 GetProperty(String, BindingFlags) 的方法多載,並加入 BindingFlags.DeclaredOnly 旗標,將搜尋限制為不會繼承的成員。To resolve the ambiguity, use the GetProperty(String, BindingFlags) method overload and add the BindingFlags.DeclaredOnly flag to restrict the search to members that are not inherited.

索引子和預設屬性Indexers and Default Properties

Visual Basic 2005Visual Basic 2005Visual C# 2005Visual C# 2005Visual C++ 2005Visual C++ 2005 具有存取索引屬性的簡化語法,並允許一個索引屬性作為其類型的預設值。, Visual C# 2005Visual C# 2005, and Visual C++ 2005Visual C++ 2005 have simplified syntax for accessing indexed properties and allow one indexed property to be a default for its type. 例如,如果變數 myList 參考 ArrayList,則語法 myList[3] (Visual Basic 中的myList(3))會抓取索引為3的元素。For example, if the variable myList refers to an ArrayList, the syntax myList[3] (myList(3) in Visual Basic) retrieves the element with the index of 3. 您可以多載屬性。You can overload the property.

在C#中,這項功能稱為「索引子」,而且不能依名稱參考。In C#, this feature is called an indexer and cannot be referred to by name. 根據預設, C#索引子會在中繼資料中顯示為名為 "Item" 的索引屬性。By default, a C# indexer appears in metadata as an indexed property named "Item". 不過,類別庫開發人員可以使用 IndexerNameAttribute 屬性來變更中繼資料中的索引子名稱。However, a class library developer can use the IndexerNameAttribute attribute to change the name of the indexer in the metadata. 例如,String 類別具有名為 Chars[]的索引子。For example, the String class has an indexer named Chars[]. 使用以外C#的語言建立的索引屬性,也可以有專案以外的名稱。Indexed properties created using languages other than C# can have names other than Item, as well.

若要判斷類型是否有預設屬性,請使用 GetCustomAttributes(Type, Boolean) 方法來測試 DefaultMemberAttribute 屬性。To determine whether a type has a default property, use the GetCustomAttributes(Type, Boolean) method to test for the DefaultMemberAttribute attribute. 如果類型具有 DefaultMemberAttributeMemberName 屬性會傳回預設屬性的名稱。If the type has DefaultMemberAttribute, the MemberName property returns the name of the default property.

See also

GetProperty(String, BindingFlags)

使用指定的繫結條件約束搜尋指定的屬性。Searches for the specified property, using the specified binding constraints.

public:
 virtual System::Reflection::PropertyInfo ^ GetProperty(System::String ^ name, System::Reflection::BindingFlags bindingAttr);
public System.Reflection.PropertyInfo GetProperty (string name, System.Reflection.BindingFlags bindingAttr);
abstract member GetProperty : string * System.Reflection.BindingFlags -> System.Reflection.PropertyInfo
override this.GetProperty : string * System.Reflection.BindingFlags -> System.Reflection.PropertyInfo
Public Function GetProperty (name As String, bindingAttr As BindingFlags) As PropertyInfo

Parameters

name
String

字串,包含要取得的屬性名稱。The string containing the name of the property to get.

bindingAttr
BindingFlags

列舉值的位元組合,用來指定搜尋的執行方式。A bitwise combination of the enumeration values that specify how the search is conducted.

-或--or- 要傳回 nullDefaultDefault to return null.

Returns

PropertyInfo

代表符合指定之需求屬性的物件 (如有找到);否則為 nullAn object representing the property that matches the specified requirements, if found; otherwise, null.

Implements

Exceptions

找到一個以上的屬性,其具有指定名稱,且符合指定繫結條件約束。More than one property is found with the specified name and matching the specified binding constraints.

namenullname is null.

Examples

下列範例會抓取使用者定義類別的型別,抓取該類別的屬性,並根據指定的系結條件約束顯示內容名稱。The following example retrieves the type of a user-defined class, retrieves a property of that class and displays the property name in accordance with the specified binding constraints.

using namespace System;
using namespace System::Reflection;
ref class MyClass
{
private:
   int myProperty;

public:

   property int MyProperty 
   {
      // Declare MyProperty.
      int get()
      {
         return myProperty;
      }

      void set( int value )
      {
         myProperty = value;
      }
   }
};

int main()
{
   try
   {
      // Get Type object of MyClass.
      Type^ myType = MyClass::typeid;
      
      // Get the PropertyInfo by passing the property name and specifying the BindingFlags.
      PropertyInfo^ myPropInfo = myType->GetProperty( "MyProperty", static_cast<BindingFlags>(BindingFlags::Public | BindingFlags::Instance) );
      
      // Display Name propety to console.
      Console::WriteLine( "{0} is a property of MyClass.", myPropInfo->Name );
   }
   catch ( NullReferenceException^ e ) 
   {
      Console::WriteLine( "MyProperty does not exist in MyClass. {0}", e->Message );
   }
}

using System;
using System.Reflection;
class MyClass
{
    private int myProperty;
    // Declare MyProperty.
    public int MyProperty
    {
        get
        {
            return myProperty;
        }
        set
        {
            myProperty=value;
        }
    }
}
public class MyTypeClass
{
    public static void Main(string[] args)
    {
        try
        {
            // Get Type object of MyClass.
            Type myType=typeof(MyClass);
            // Get the PropertyInfo by passing the property name and specifying the BindingFlags.
            PropertyInfo myPropInfo = myType.GetProperty("MyProperty", BindingFlags.Public | BindingFlags.Instance);
            // Display Name propety to console.
            Console.WriteLine("{0} is a property of MyClass.", myPropInfo.Name);
        }
        catch(NullReferenceException e)
        {
            Console.WriteLine("MyProperty does not exist in MyClass." +e.Message);
        }
    }
}

Imports System.Reflection
Module Module1
    Public Class MyClass1
        Private myProperty1 As Integer
        ' Declare MyProperty.
        Public Property MyProperty() As Integer
            Get
                Return myProperty1
            End Get
            Set(ByVal Value As Integer)
                myProperty1 = Value
            End Set
        End Property
        Public Shared Sub Main()
            Try
                ' Get a Type object corresponding to MyClass.
                Dim myType As Type = GetType(MyClass1)
                ' Get a PropertyInfo object by passing property name and specifying BindingFlags.
                Dim myPropInfo As PropertyInfo = myType.GetProperty("MyProperty", BindingFlags.Public Or BindingFlags.Instance)
                ' Display the Name property.
                Console.WriteLine("{0} is a property of MyClass.", myPropInfo.Name)
            Catch e As NullReferenceException
                Console.WriteLine("MyProperty does not exist in MyClass.", e.Message.ToString())
            End Try
        End Sub
    End Class
End Module 'Module1

Remarks

如果屬性至少有一個公用存取子,則會將其視為公開給反映。A property is considered public to reflection if it has at least one accessor that is public. 否則,屬性會被視為私用,而且您必須|使用| BindingFlags.NonPublic BindingFlags.Instance BindingFlags.Static (在 Visual Basic 中,使用 Or來結合值)以取得它。Otherwise the property is considered private, and you must use BindingFlags.NonPublic | BindingFlags.Instance | BindingFlags.Static (in Visual Basic, combine the values using Or) to get it.

下列 BindingFlags 篩選旗標可以用來定義要包含在搜尋中的屬性:The following BindingFlags filter flags can be used to define which properties to include in the search:

  • 您必須指定 BindingFlags.InstanceBindingFlags.Static,才能取得傳回。You must specify either BindingFlags.Instance or BindingFlags.Static in order to get a return.

  • 指定要在搜尋中包含公用屬性 BindingFlags.PublicSpecify BindingFlags.Public to include public properties in the search.

  • 指定要在搜尋中包含非公用屬性(也就是私用、內部和受保護的屬性) BindingFlags.NonPublicSpecify BindingFlags.NonPublic to include non-public properties (that is, private, internal, and protected properties) in the search.

  • 指定 BindingFlags.FlattenHierarchy 在階層中包含 publicprotected 靜態成員;不包含繼承類別中 private 的靜態成員。Specify BindingFlags.FlattenHierarchy to include public and protected static members up the hierarchy; private static members in inherited classes are not included.

下列 BindingFlags 的修飾詞旗標可以用來變更搜尋的運作方式:The following BindingFlags modifier flags can be used to change how the search works:

  • BindingFlags.IgnoreCase 以忽略 name的大小寫。BindingFlags.IgnoreCase to ignore the case of name.

  • BindingFlags.DeclaredOnly 只搜尋 Type上宣告的屬性,而不是直接繼承的屬性。BindingFlags.DeclaredOnly to search only the properties declared on the Type, not properties that were simply inherited.

如需相關資訊,請參閱 System.Reflection.BindingFlagsSee System.Reflection.BindingFlags for more information.

如果目前的 Type 代表結構化的泛型型別,這個方法會傳回 PropertyInfo,其中的型別參數是由適當的型別引數所取代。If the current Type represents a constructed generic type, this method returns the PropertyInfo with the type parameters replaced by the appropriate type arguments.

如果目前 Type 表示泛型型別或泛型方法定義中的類型參數,這個方法會搜尋類別條件約束的屬性。If the current Type represents a type parameter in the definition of a generic type or generic method, this method searches the properties of the class constraint.

發生 AmbiguousMatchException 的情況包括下列各項:Situations in which AmbiguousMatchException occurs include the following:

  • 類型包含兩個具有相同名稱但參數數目不同的索引屬性。A type contains two indexed properties that have the same name but different numbers of parameters. 若要解決不明確的問題,請使用指定參數類型之 GetProperty 方法的多載。To resolve the ambiguity, use an overload of the GetProperty method that specifies parameter types.

  • 衍生的型別會宣告一個屬性,它會使用 new 修飾詞(在 Visual Basic 中Shadows)來隱藏具有相同名稱的繼承屬性。A derived type declares a property that hides an inherited property with the same name, using the new modifier (Shadows in Visual Basic). 若要解決不明確的問題,請包含 BindingFlags.DeclaredOnly,將搜尋限制為不會繼承的成員。To resolve the ambiguity, include BindingFlags.DeclaredOnly to restrict the search to members that are not inherited.

索引子和預設屬性Indexers and Default Properties

Visual Basic 2005Visual Basic 2005Visual C# 2005Visual C# 2005Visual C++ 2005Visual C++ 2005 具有存取索引屬性的簡化語法,並允許一個索引屬性作為其類型的預設值。, Visual C# 2005Visual C# 2005, and Visual C++ 2005Visual C++ 2005 have simplified syntax for accessing indexed properties and allow one indexed property to be a default for its type. 例如,如果變數 myList 參考 ArrayList,則語法 myList[3] (Visual Basic 中的myList(3))會抓取索引為3的元素。For example, if the variable myList refers to an ArrayList, the syntax myList[3] (myList(3) in Visual Basic) retrieves the element with the index of 3. 您可以多載屬性。You can overload the property.

在C#中,這項功能稱為「索引子」,而且不能依名稱參考。In C#, this feature is called an indexer and cannot be referred to by name. 根據預設, C#索引子會在中繼資料中顯示為名為 "Item" 的索引屬性。By default, a C# indexer appears in metadata as an indexed property named "Item". 不過,類別庫開發人員可以使用 IndexerNameAttribute 屬性來變更中繼資料中的索引子名稱。However, a class library developer can use the IndexerNameAttribute attribute to change the name of the indexer in the metadata. 例如,String 類別具有名為 Chars[]的索引子。For example, the String class has an indexer named Chars[]. 使用以外C#的語言建立的索引屬性,也可以有專案以外的名稱。Indexed properties created using languages other than C# can have names other than Item, as well.

若要判斷類型是否有預設屬性,請使用 GetCustomAttributes(Type, Boolean) 方法來測試 DefaultMemberAttribute 屬性。To determine whether a type has a default property, use the GetCustomAttributes(Type, Boolean) method to test for the DefaultMemberAttribute attribute. 如果類型具有 DefaultMemberAttributeMemberName 屬性會傳回預設屬性的名稱。If the type has DefaultMemberAttribute, the MemberName property returns the name of the default property.

See also

GetProperty(String, Type)

搜尋具有指定名稱和傳回類型的公用屬性。Searches for the public property with the specified name and return type.

public:
 System::Reflection::PropertyInfo ^ GetProperty(System::String ^ name, Type ^ returnType);
public:
 virtual System::Reflection::PropertyInfo ^ GetProperty(System::String ^ name, Type ^ returnType);
public System.Reflection.PropertyInfo GetProperty (string name, Type returnType);
member this.GetProperty : string * Type -> System.Reflection.PropertyInfo
abstract member GetProperty : string * Type -> System.Reflection.PropertyInfo
override this.GetProperty : string * Type -> System.Reflection.PropertyInfo
Public Function GetProperty (name As String, returnType As Type) As PropertyInfo

Parameters

name
String

字串,包含要取得的公用屬性名稱。The string containing the name of the public property to get.

returnType
Type

屬性的傳回類型。The return type of the property.

Returns

PropertyInfo

物件,代表具有指定之名稱的公用屬性 (如有找到),否則為 nullAn object representing the public property with the specified name, if found; otherwise, null.

Implements

Exceptions

找到一個以上具有指定名稱的屬性。More than one property is found with the specified name.

namenull,或 returnTypenullname is null, or returnType is null.

Examples

下列範例會定義具有一個屬性的類別,並抓取屬性的名稱和類型。The following example defines a class with one property and retrieves the name and type of the property.

using namespace System;
using namespace System::Reflection;
ref class MyClass1
{
private:
   String^ myMessage;

public:

   property String^ MyProperty1 
   {
      String^ get()
      {
         return myMessage;
      }

      void set( String^ value )
      {
         myMessage = value;
      }
   }
};

int main()
{
   try
   {
      Type^ myType = MyClass1::typeid;
      
      // Get the PropertyInfo Object* representing MyProperty1.
      PropertyInfo^ myStringProperties1 = myType->GetProperty( "MyProperty1", String::typeid );
      Console::WriteLine( "The name of the first property of MyClass1 is {0}.", myStringProperties1->Name );
      Console::WriteLine( "The type of the first property of MyClass1 is {0}.", myStringProperties1->PropertyType );
   }
   catch ( ArgumentNullException^ e ) 
   {
      Console::WriteLine( "ArgumentNullException : {0}", e->Message );
   }
   catch ( AmbiguousMatchException^ e ) 
   {
      Console::WriteLine( "AmbiguousMatchException : {0}", e->Message );
   }
   catch ( NullReferenceException^ e ) 
   {
      Console::WriteLine( "Source : {0}", e->Source );
      Console::WriteLine( "Message : {0}", e->Message );
   }
   //Output:
   //The name of the first property of MyClass1 is MyProperty1.
   //The type of the first property of MyClass1 is System.String.

}

using System;
using System.Reflection;

class MyClass1
{
    String myMessage="Hello World.";
    public string MyProperty1
    {
        get
        {			
            return myMessage;
        }
        set
        {
            myMessage =value;
        }			
    }
}
class TestClass
{
    static void Main()
    {
        try
        {	
            Type myType = typeof(MyClass1);
            // Get the PropertyInfo object representing MyProperty1.
            PropertyInfo myStringProperties1 = myType.GetProperty("MyProperty1",
                typeof(string));
            Console.WriteLine("The name of the first property of MyClass1 is {0}.", myStringProperties1.Name);
            Console.WriteLine("The type of the first property of MyClass1 is {0}.", myStringProperties1.PropertyType);
        }
        catch(ArgumentNullException e)
        {
            Console.WriteLine("ArgumentNullException :"+e.Message);
        }
        catch(AmbiguousMatchException e)
        {
            Console.WriteLine("AmbiguousMatchException :"+e.Message);
        }
        catch(NullReferenceException e)
        {
            Console.WriteLine("Source : {0}" , e.Source);
            Console.WriteLine("Message : {0}" , e.Message);
        }
    //Output:
    //The name of the first property of MyClass1 is MyProperty1.
    //The type of the first property of MyClass1 is System.String.
    }
}
Imports System.Reflection
Class MyClass1
    Private myMessage As [String] = "Hello World."
    Public Property MyProperty1() As String
        Get
            Return myMessage
        End Get
        Set(ByVal Value As String)
            myMessage = Value
        End Set
    End Property
End Class

Class TestClass
    Shared Sub Main()
        Try
            Dim myType As Type = GetType(MyClass1)
            ' Get the PropertyInfo object representing MyProperty1. 
            Dim myStringProperties1 As PropertyInfo = myType.GetProperty("MyProperty1", GetType(String))
            Console.WriteLine("The name of the first property of MyClass1 is {0}.", myStringProperties1.Name)
            Console.WriteLine("The type of the first property of MyClass1 is {0}.", myStringProperties1.PropertyType.ToString())
        Catch e As ArgumentNullException
            Console.WriteLine("ArgumentNullException :" + e.Message.ToString())
        Catch e As AmbiguousMatchException
            Console.WriteLine("AmbiguousMatchException :" + e.Message.ToString())
        Catch e As NullReferenceException
            Console.WriteLine("Source : {0}", e.Source.ToString())
            Console.WriteLine("Message : {0}", e.Message.ToString())
        End Try
    'Output:
    'The name of the first property of MyClass1 is MyProperty1.
    'The type of the first property of MyClass1 is System.String.

    End Sub
End Class

Remarks

如果屬性至少有一個公用存取子,則會將其視為公開給反映。A property is considered public to reflection if it has at least one accessor that is public. 否則,屬性會被視為私用,而且您必須|使用| BindingFlags.NonPublic BindingFlags.Instance BindingFlags.Static (在 Visual Basic 中,使用 Or來結合值)以取得它。Otherwise the property is considered private, and you must use BindingFlags.NonPublic | BindingFlags.Instance | BindingFlags.Static (in Visual Basic, combine the values using Or) to get it.

name 的搜尋會區分大小寫。The search for name is case-sensitive. 搜尋包括公用靜態和公用實例屬性。The search includes public static and public instance properties.

如果目前的 Type 代表結構化的泛型型別,這個方法會傳回 PropertyInfo,其中的型別參數是由適當的型別引數所取代。If the current Type represents a constructed generic type, this method returns the PropertyInfo with the type parameters replaced by the appropriate type arguments.

如果目前 Type 表示泛型型別或泛型方法定義中的類型參數,這個方法會搜尋類別條件約束的屬性。If the current Type represents a type parameter in the definition of a generic type or generic method, this method searches the properties of the class constraint.

索引子和預設屬性Indexers and Default Properties

Visual Basic 2005Visual Basic 2005Visual C# 2005Visual C# 2005Visual C++ 2005Visual C++ 2005 具有存取索引屬性的簡化語法,並允許一個索引屬性作為其類型的預設值。, Visual C# 2005Visual C# 2005, and Visual C++ 2005Visual C++ 2005 have simplified syntax for accessing indexed properties and allow one indexed property to be a default for its type. 例如,如果變數 myList 參考 ArrayList,則語法 myList[3] (Visual Basic 中的myList(3))會抓取索引為3的元素。For example, if the variable myList refers to an ArrayList, the syntax myList[3] (myList(3) in Visual Basic) retrieves the element with the index of 3. 您可以多載屬性。You can overload the property.

在C#中,這項功能稱為「索引子」,而且不能依名稱參考。In C#, this feature is called an indexer and cannot be referred to by name. 根據預設, C#索引子會在中繼資料中顯示為名為 "Item" 的索引屬性。By default, a C# indexer appears in metadata as an indexed property named "Item". 不過,類別庫開發人員可以使用 IndexerNameAttribute 屬性來變更中繼資料中的索引子名稱。However, a class library developer can use the IndexerNameAttribute attribute to change the name of the indexer in the metadata. 例如,String 類別具有名為 Chars[]的索引子。For example, the String class has an indexer named Chars[]. 使用以外C#的語言建立的索引屬性,也可以有專案以外的名稱。Indexed properties created using languages other than C# can have names other than Item, as well.

若要判斷類型是否有預設屬性,請使用 GetCustomAttributes(Type, Boolean) 方法來測試 DefaultMemberAttribute 屬性。To determine whether a type has a default property, use the GetCustomAttributes(Type, Boolean) method to test for the DefaultMemberAttribute attribute. 如果類型具有 DefaultMemberAttributeMemberName 屬性會傳回預設屬性的名稱。If the type has DefaultMemberAttribute, the MemberName property returns the name of the default property.

See also

GetProperty(String, Type[])

搜尋指定的公用屬性,其參數符合指定的引數類型。Searches for the specified public property whose parameters match the specified argument types.

public:
 System::Reflection::PropertyInfo ^ GetProperty(System::String ^ name, cli::array <Type ^> ^ types);
public:
 virtual System::Reflection::PropertyInfo ^ GetProperty(System::String ^ name, cli::array <Type ^> ^ types);
public System.Reflection.PropertyInfo GetProperty (string name, Type[] types);
member this.GetProperty : string * Type[] -> System.Reflection.PropertyInfo
abstract member GetProperty : string * Type[] -> System.Reflection.PropertyInfo
override this.GetProperty : string * Type[] -> System.Reflection.PropertyInfo
Public Function GetProperty (name As String, types As Type()) As PropertyInfo

Parameters

name
String

字串,包含要取得的公用屬性名稱。The string containing the name of the public property to get.

types
Type[]

Type 物件的陣列,代表所要取得之索引屬性的參數數目、順序和類型。An array of Type objects representing the number, order, and type of the parameters for the indexed property to get.

-或--or- 用以取得未編製索引的屬性之 Type 類型的空陣列 (也就是,Type[] types = new Type[0])。An empty array of the type Type (that is, Type[] types = new Type[0]) to get a property that is not indexed.

Returns

PropertyInfo

代表其參數符合指定之引數類型的公用屬性物件 (如有找到),否則為 nullAn object representing the public property whose parameters match the specified argument types, if found; otherwise, null.

Implements

Exceptions

找到一個以上具有指定名稱,且符合指定引數類型的屬性。More than one property is found with the specified name and matching the specified argument types.

namenullname is null.

-或--or- typesnulltypes is null.

types 是多維度。types is multidimensional.

types 的項目是 nullAn element of types is null.

Examples

下列範例會抓取使用者定義類別的 Type 物件、抓取該類別的屬性,並依傳遞給 GetProperty的引數所指定,顯示內容的屬性名稱和類型。The following example retrieves the Type object of a user-defined class, retrieves the property of that class, and displays the property name and type of the property as specified by the arguments passed to GetProperty.

using namespace System;
using namespace System::Reflection;
ref class MyClass1
{
private:
   array<int, 2>^myArray;

public:

   property int Item [int, int]
   {

      // Declare an indexer.
      int get( int i, int j )
      {
         return myArray[ i,j ];
      }

      void set( int i, int j, int value )
      {
         myArray[ i,j ] = value;
      }

   }

};

int main()
{
   try
   {
      
      // Get the Type object.
      Type^ myType = MyClass1::typeid;
      array<Type^>^myTypeArr = gcnew array<Type^>(2);
      
      // Create an instance of a Type array.
      myTypeArr->SetValue( int::typeid, 0 );
      myTypeArr->SetValue( int::typeid, 1 );
      
      // Get the PropertyInfo object for the indexed property Item, which has two integer parameters.
      PropertyInfo^ myPropInfo = myType->GetProperty( "Item", myTypeArr );
      
      // Display the property.
      Console::WriteLine( "The {0} property exists in MyClass1.", myPropInfo );
   }
   catch ( NullReferenceException^ e ) 
   {
      Console::WriteLine( "An exception occurred." );
      Console::WriteLine( "Source : {0}", e->Source );
      Console::WriteLine( "Message : {0}", e->Message );
   }

}


using System;
using System.Reflection;
class MyClass1
{
    private int [,] myArray = {{1,2},{3,4}};
    // Declare an indexer.
    public int this [int i,int j]
    {
        get
        {
            return myArray[i,j];
        }
        set
        {
            myArray[i,j] = value;
        }
    }
}
public class MyTypeClass
{
    public static void Main(string[] args)
    {
        try
        {
            // Get the Type object.
            Type myType=typeof(MyClass1);
            Type[] myTypeArr = new Type[2];
            // Create an instance of a Type array.
            myTypeArr.SetValue(typeof(int),0);
            myTypeArr.SetValue(typeof(int),1);
            // Get the PropertyInfo object for the indexed property Item, which has two integer parameters.
            PropertyInfo myPropInfo = myType.GetProperty("Item", myTypeArr);
            // Display the property.
            Console.WriteLine("The {0} property exists in MyClass1.", myPropInfo.ToString());
        }
        catch(NullReferenceException e)
        {
            Console.WriteLine("An exception occurred.");
            Console.WriteLine("Source : {0}" , e.Source);
            Console.WriteLine("Message : {0}" , e.Message);
        }
    }
}
Imports System.Reflection

Module Module1
    Class MyClass1
        Private myArray As Integer(,) = {{1, 2}, {3, 4}}
        ' Declare an indexer.
        Default Public Property Item(ByVal i As Integer, ByVal j As Integer) As Integer
            Get
                Return myArray(i, j)
            End Get
            Set(ByVal Value As Integer)

                myArray(i, j) = Value
            End Set
        End Property
    End Class

    Public Class MyTypeClass
        Public Shared Sub Main()
            Try
                ' Get the Type Object.
                Dim myType As Type = GetType(MyClass1)
                Dim myTypeArr(1) As Type
                ' Create an instance of a Type array.
                myTypeArr.SetValue(GetType(Integer), 0)
                myTypeArr.SetValue(GetType(Integer), 1)
                ' Get the PropertyInfo object for the indexed property Item, which has two integer parameters. 
                Dim myPropInfo As PropertyInfo = myType.GetProperty("Item", myTypeArr)
                ' Display the property.
                Console.WriteLine("The {0} property exists in MyClass1.", myPropInfo.ToString())
            Catch e As NullReferenceException
                Console.WriteLine("An exception occurred.")
                Console.WriteLine("Source : {0}", e.Source.ToString())
                Console.WriteLine("Message : {0}", e.Message.ToString())
            End Try
        End Sub
    End Class
End Module 'Module1

Remarks

如果屬性至少有一個公用存取子,則會將其視為公開給反映。A property is considered public to reflection if it has at least one accessor that is public. 否則,屬性會被視為私用,而且您必須|使用| BindingFlags.NonPublic BindingFlags.Instance BindingFlags.Static (在 Visual Basic 中,使用 Or來結合值)以取得它。Otherwise the property is considered private, and you must use BindingFlags.NonPublic | BindingFlags.Instance | BindingFlags.Static (in Visual Basic, combine the values using Or) to get it.

name 的搜尋會區分大小寫。The search for name is case-sensitive. 搜尋包括公用靜態和公用實例屬性。The search includes public static and public instance properties.

如果目前的 Type 代表結構化的泛型型別,這個方法會傳回 PropertyInfo,其中的型別參數是由適當的型別引數所取代。If the current Type represents a constructed generic type, this method returns the PropertyInfo with the type parameters replaced by the appropriate type arguments.

如果目前 Type 表示泛型型別或泛型方法定義中的類型參數,這個方法會搜尋類別條件約束的屬性。If the current Type represents a type parameter in the definition of a generic type or generic method, this method searches the properties of the class constraint.

索引子和預設屬性Indexers and Default Properties

Visual Basic 2005Visual Basic 2005Visual C# 2005Visual C# 2005Visual C++ 2005Visual C++ 2005 具有存取索引屬性的簡化語法,並允許一個索引屬性作為其類型的預設值。, Visual C# 2005Visual C# 2005, and Visual C++ 2005Visual C++ 2005 have simplified syntax for accessing indexed properties and allow one indexed property to be a default for its type. 例如,如果變數 myList 參考 ArrayList,則語法 myList[3] (Visual Basic 中的myList(3))會抓取索引為3的元素。For example, if the variable myList refers to an ArrayList, the syntax myList[3] (myList(3) in Visual Basic) retrieves the element with the index of 3. 您可以多載屬性。You can overload the property.

在C#中,這項功能稱為「索引子」,而且不能依名稱參考。In C#, this feature is called an indexer and cannot be referred to by name. 根據預設, C#索引子會在中繼資料中顯示為名為 "Item" 的索引屬性。By default, a C# indexer appears in metadata as an indexed property named "Item". 不過,類別庫開發人員可以使用 IndexerNameAttribute 屬性來變更中繼資料中的索引子名稱。However, a class library developer can use the IndexerNameAttribute attribute to change the name of the indexer in the metadata. 例如,String 類別具有名為 Chars[]的索引子。For example, the String class has an indexer named Chars[]. 使用以外C#的語言建立的索引屬性,也可以有專案以外的名稱。Indexed properties created using languages other than C# can have names other than Item, as well.

若要判斷類型是否有預設屬性,請使用 GetCustomAttributes(Type, Boolean) 方法來測試 DefaultMemberAttribute 屬性。To determine whether a type has a default property, use the GetCustomAttributes(Type, Boolean) method to test for the DefaultMemberAttribute attribute. 如果類型具有 DefaultMemberAttributeMemberName 屬性會傳回預設屬性的名稱。If the type has DefaultMemberAttribute, the MemberName property returns the name of the default property.

See also

GetProperty(String, Type, Type[])

搜尋指定的公用屬性,其參數符合指定的引數類型。Searches for the specified public property whose parameters match the specified argument types.

public:
 System::Reflection::PropertyInfo ^ GetProperty(System::String ^ name, Type ^ returnType, cli::array <Type ^> ^ types);
public:
 virtual System::Reflection::PropertyInfo ^ GetProperty(System::String ^ name, Type ^ returnType, cli::array <Type ^> ^ types);
public System.Reflection.PropertyInfo GetProperty (string name, Type returnType, Type[] types);
member this.GetProperty : string * Type * Type[] -> System.Reflection.PropertyInfo
abstract member GetProperty : string * Type * Type[] -> System.Reflection.PropertyInfo
override this.GetProperty : string * Type * Type[] -> System.Reflection.PropertyInfo
Public Function GetProperty (name As String, returnType As Type, types As Type()) As PropertyInfo

Parameters

name
String

字串,包含要取得的公用屬性名稱。The string containing the name of the public property to get.

returnType
Type

屬性的傳回類型。The return type of the property.

types
Type[]

Type 物件的陣列,代表所要取得之索引屬性的參數數目、順序和類型。An array of Type objects representing the number, order, and type of the parameters for the indexed property to get.

-或--or- 用以取得未編製索引的屬性之 Type 類型的空陣列 (也就是,Type[] types = new Type[0])。An empty array of the type Type (that is, Type[] types = new Type[0]) to get a property that is not indexed.

Returns

PropertyInfo

代表其參數符合指定之引數類型的公用屬性物件 (如有找到),否則為 nullAn object representing the public property whose parameters match the specified argument types, if found; otherwise, null.

Implements

Exceptions

找到一個以上具有指定名稱,且符合指定引數類型的屬性。More than one property is found with the specified name and matching the specified argument types.

namenullname is null.

-或--or- typesnulltypes is null.

types 是多維度。types is multidimensional.

types 的項目是 nullAn element of types is null.

Remarks

如果屬性至少有一個公用存取子,則會將其視為公開給反映。A property is considered public to reflection if it has at least one accessor that is public. 否則,屬性會被視為私用,而且您必須|使用| BindingFlags.NonPublic BindingFlags.Instance BindingFlags.Static (在 Visual Basic 中,使用 Or來結合值)以取得它。Otherwise the property is considered private, and you must use BindingFlags.NonPublic | BindingFlags.Instance | BindingFlags.Static (in Visual Basic, combine the values using Or) to get it.

name 的搜尋會區分大小寫。The search for name is case-sensitive. 搜尋包括公用靜態和公用實例屬性。The search includes public static and public instance properties.

如果目前的 Type 代表結構化的泛型型別,這個方法會傳回 PropertyInfo,其中的型別參數是由適當的型別引數所取代。If the current Type represents a constructed generic type, this method returns the PropertyInfo with the type parameters replaced by the appropriate type arguments.

如果目前 Type 表示泛型型別或泛型方法定義中的類型參數,這個方法會搜尋類別條件約束的屬性。If the current Type represents a type parameter in the definition of a generic type or generic method, this method searches the properties of the class constraint.

索引子和預設屬性Indexers and Default Properties

Visual Basic 2005Visual Basic 2005Visual C# 2005Visual C# 2005Visual C++ 2005Visual C++ 2005 具有存取索引屬性的簡化語法,並允許一個索引屬性作為其類型的預設值。, Visual C# 2005Visual C# 2005, and Visual C++ 2005Visual C++ 2005 have simplified syntax for accessing indexed properties and allow one indexed property to be a default for its type. 例如,如果變數 myList 參考 ArrayList,則語法 myList[3] (Visual Basic 中的myList(3))會抓取索引為3的元素。For example, if the variable myList refers to an ArrayList, the syntax myList[3] (myList(3) in Visual Basic) retrieves the element with the index of 3. 您可以多載屬性。You can overload the property.

在C#中,這項功能稱為「索引子」,而且不能依名稱參考。In C#, this feature is called an indexer and cannot be referred to by name. 根據預設, C#索引子會在中繼資料中顯示為名為 "Item" 的索引屬性。By default, a C# indexer appears in metadata as an indexed property named "Item". 不過,類別庫開發人員可以使用 IndexerNameAttribute 屬性來變更中繼資料中的索引子名稱。However, a class library developer can use the IndexerNameAttribute attribute to change the name of the indexer in the metadata. 例如,String 類別具有名為 Chars[]的索引子。For example, the String class has an indexer named Chars[]. 使用以外C#的語言建立的索引屬性,也可以有專案以外的名稱。Indexed properties created using languages other than C# can have names other than Item, as well.

若要判斷類型是否有預設屬性,請使用 GetCustomAttributes(Type, Boolean) 方法來測試 DefaultMemberAttribute 屬性。To determine whether a type has a default property, use the GetCustomAttributes(Type, Boolean) method to test for the DefaultMemberAttribute attribute. 如果類型具有 DefaultMemberAttributeMemberName 屬性會傳回預設屬性的名稱。If the type has DefaultMemberAttribute, the MemberName property returns the name of the default property.

See also

GetProperty(String, Type, Type[], ParameterModifier[])

搜尋指定的公用屬性,其參數符合指定的引數類型和修飾詞。Searches for the specified public property whose parameters match the specified argument types and modifiers.

public:
 System::Reflection::PropertyInfo ^ GetProperty(System::String ^ name, Type ^ returnType, cli::array <Type ^> ^ types, cli::array <System::Reflection::ParameterModifier> ^ modifiers);
public:
 virtual System::Reflection::PropertyInfo ^ GetProperty(System::String ^ name, Type ^ returnType, cli::array <Type ^> ^ types, cli::array <System::Reflection::ParameterModifier> ^ modifiers);
public System.Reflection.PropertyInfo GetProperty (string name, Type returnType, Type[] types, System.Reflection.ParameterModifier[] modifiers);
member this.GetProperty : string * Type * Type[] * System.Reflection.ParameterModifier[] -> System.Reflection.PropertyInfo
abstract member GetProperty : string * Type * Type[] * System.Reflection.ParameterModifier[] -> System.Reflection.PropertyInfo
override this.GetProperty : string * Type * Type[] * System.Reflection.ParameterModifier[] -> System.Reflection.PropertyInfo
Public Function GetProperty (name As String, returnType As Type, types As Type(), modifiers As ParameterModifier()) As PropertyInfo

Parameters

name
String

字串,包含要取得的公用屬性名稱。The string containing the name of the public property to get.

returnType
Type

屬性的傳回類型。The return type of the property.

types
Type[]

Type 物件的陣列,代表所要取得之索引屬性的參數數目、順序和類型。An array of Type objects representing the number, order, and type of the parameters for the indexed property to get.

-或--or- 用以取得未編製索引的屬性之 Type 類型的空陣列 (也就是,Type[] types = new Type[0])。An empty array of the type Type (that is, Type[] types = new Type[0]) to get a property that is not indexed.

modifiers
ParameterModifier[]

ParameterModifier 物件的陣列,代表在 types 陣列中與對應項目關聯的屬性。An array of ParameterModifier objects representing the attributes associated with the corresponding element in the types array. 預設的繫結器不會處理這個參數。The default binder does not process this parameter.

Returns

PropertyInfo

物件,代表符合指定之需求的公用屬性 (如有找到),否則為 nullAn object representing the public property that matches the specified requirements, if found; otherwise, null.

Implements

Exceptions

找到一個以上具有指定名稱,且符合指定引數類型和修飾詞的屬性。More than one property is found with the specified name and matching the specified argument types and modifiers.

namenullname is null.

-或--or- typesnulltypes is null.

types 是多維度。types is multidimensional.

-或--or- modifiers 是多維度。modifiers is multidimensional.

-或--or- typesmodifiers 的長度不同。types and modifiers do not have the same length.

types 的項目是 nullAn element of types is null.

Examples

下列範例會取得對應至 MyPropertyClassType 物件,並使用傳遞至 GetProperty 方法的引數來抓取此類別的索引屬性。The following example obtains a Type object corresponding to MyPropertyClass, and the indexed property of this class is retrieved using the arguments passed to the GetProperty method.

using namespace System;
using namespace System::Reflection;
public ref class MyPropertyClass
{
private:
   array<int, 2>^ myPropertyArray;

public:

   property int Item [int, int]
   {
      // Declare an indexer.
      int get( int i, int j )
      {
         return myPropertyArray[ i,j ];
      }

      void set( int i, int j, int value )
      {
         myPropertyArray[ i,j ] = value;
      }

   }

};

int main()
{
   try
   {
      Type^ myType = MyPropertyClass::typeid;
      array<Type^>^myTypeArray = gcnew array<Type^>(2);
      
      // Create an instance of the Type array representing the number, order
      // and type of the parameters for the property.
      myTypeArray->SetValue( int::typeid, 0 );
      myTypeArray->SetValue( int::typeid, 1 );
      
      // Search for the indexed property whose parameters match the
      // specified argument types and modifiers.
      PropertyInfo^ myPropertyInfo = myType->GetProperty( "Item", int::typeid, myTypeArray, nullptr );
      Console::WriteLine( "{0}.{1} has a property type of {2}", myType->FullName, myPropertyInfo->Name, myPropertyInfo->PropertyType );
   }
   catch ( Exception^ ex ) 
   {
      Console::WriteLine( "An exception occurred {0}", ex->Message );
   }

}

using System;
using System.Reflection;
public class MyPropertyClass
{
    private int [,] myPropertyArray = new int[10,10];
    // Declare an indexer.
    public int this [int i,int j]
    {
        get
        {
            return myPropertyArray[i,j];
        }
        set
        {
            myPropertyArray[i,j] = value;
        }
    }
}
public class MyTypeClass
{
    public static void Main()
    {
        try
        {
            Type myType=typeof(MyPropertyClass);
            Type[] myTypeArray = new Type[2];
            // Create an instance of the Type array representing the number, order
            // and type of the parameters for the property.
            myTypeArray.SetValue(typeof(int),0);
            myTypeArray.SetValue(typeof(int),1);
            // Search for the indexed property whose parameters match the
            // specified argument types and modifiers.
            PropertyInfo myPropertyInfo = myType.GetProperty("Item",
                typeof(int),myTypeArray,null);
            Console.WriteLine(myType.FullName + "." + myPropertyInfo.Name +
                " has a property type of " + myPropertyInfo.PropertyType);
         }
        catch(Exception ex)
        {
            Console.WriteLine("An exception occurred " + ex.Message);
        }
    }
}
Imports System.Reflection

Public Class MyPropertyClass
    Private myPropertyArray(9, 9) As Integer
    ' Declare an indexer.
    Default Public Property Item(ByVal i As Integer, ByVal j As Integer) As Integer
        Get
            Return myPropertyArray(i, j)
        End Get
        Set(ByVal Value As Integer)
            myPropertyArray(i, j) = Value
        End Set
    End Property
End Class

Public Class MyTypeClass
    Public Shared Sub Main()
        Try
            Dim myType As Type = GetType(MyPropertyClass)
            Dim myTypeArray(1) As Type
            ' Create an instance of a Type array representing the number, order 
            ' and type of the parameters for the property.
            myTypeArray.SetValue(GetType(Integer), 0)
            myTypeArray.SetValue(GetType(Integer), 1)
            ' Search for the indexed property whose parameters match the
            ' specified argument types and modifiers.
            Dim myPropertyInfo As PropertyInfo = myType.GetProperty("Item", _
                  GetType(Integer), myTypeArray, Nothing)
            Console.WriteLine(myType.FullName + "." + myPropertyInfo.Name + _
                  " has a property  type of " + myPropertyInfo.PropertyType.ToString())
        Catch ex As Exception
            Console.WriteLine("An exception occurred " + ex.Message.ToString())
        End Try
    End Sub
End Class

Remarks

如果屬性至少有一個公用存取子,則會將其視為公開給反映。A property is considered public to reflection if it has at least one accessor that is public. 否則,屬性會被視為私用,而且您必須|使用| BindingFlags.NonPublic BindingFlags.Instance BindingFlags.Static (在 Visual Basic 中,使用 Or來結合值)以取得它。Otherwise the property is considered private, and you must use BindingFlags.NonPublic | BindingFlags.Instance | BindingFlags.Static (in Visual Basic, combine the values using Or) to get it.

雖然預設的系結器不會處理 ParameterModifiermodifiers 參數),但您可以使用抽象的 System.Reflection.Binder 類別來撰寫會處理 modifiers的自訂系結器。Although the default binder does not process ParameterModifier (the modifiers parameter), you can use the abstract System.Reflection.Binder class to write a custom binder that does process modifiers. 只有在透過 COM Interop 呼叫時,才會使用 ParameterModifier,而且只會處理以傳址方式傳遞的參數。ParameterModifier is only used when calling through COM interop, and only parameters that are passed by reference are handled.

name 的搜尋會區分大小寫。The search for name is case-sensitive. 搜尋包括公用靜態和公用實例屬性。The search includes public static and public instance properties.

如果目前的 Type 代表結構化的泛型型別,這個方法會傳回 PropertyInfo,其中的型別參數是由適當的型別引數所取代。If the current Type represents a constructed generic type, this method returns the PropertyInfo with the type parameters replaced by the appropriate type arguments.

如果目前 Type 表示泛型型別或泛型方法定義中的類型參數,這個方法會搜尋類別條件約束的屬性。If the current Type represents a type parameter in the definition of a generic type or generic method, this method searches the properties of the class constraint.

索引子和預設屬性Indexers and Default Properties

Visual Basic 2005Visual Basic 2005Visual C# 2005Visual C# 2005Visual C++ 2005Visual C++ 2005 具有存取索引屬性的簡化語法,並允許一個索引屬性作為其類型的預設值。, Visual C# 2005Visual C# 2005, and Visual C++ 2005Visual C++ 2005 have simplified syntax for accessing indexed properties and allow one indexed property to be a default for its type. 例如,如果變數 myList 參考 ArrayList,則語法 myList[3] (Visual Basic 中的myList(3))會抓取索引為3的元素。For example, if the variable myList refers to an ArrayList, the syntax myList[3] (myList(3) in Visual Basic) retrieves the element with the index of 3. 您可以多載屬性。You can overload the property.

在C#中,這項功能稱為「索引子」,而且不能依名稱參考。In C#, this feature is called an indexer and cannot be referred to by name. 根據預設, C#索引子會在中繼資料中顯示為名為 "Item" 的索引屬性。By default, a C# indexer appears in metadata as an indexed property named "Item". 不過,類別庫開發人員可以使用 IndexerNameAttribute 屬性來變更中繼資料中的索引子名稱。However, a class library developer can use the IndexerNameAttribute attribute to change the name of the indexer in the metadata. 例如,String 類別具有名為 Chars[]的索引子。For example, the String class has an indexer named Chars[]. 使用以外C#的語言建立的索引屬性,也可以有專案以外的名稱。Indexed properties created using languages other than C# can have names other than Item, as well.

若要判斷類型是否有預設屬性,請使用 GetCustomAttributes(Type, Boolean) 方法來測試 DefaultMemberAttribute 屬性。To determine whether a type has a default property, use the GetCustomAttributes(Type, Boolean) method to test for the DefaultMemberAttribute attribute. 如果類型具有 DefaultMemberAttributeMemberName 屬性會傳回預設屬性的名稱。If the type has DefaultMemberAttribute, the MemberName property returns the name of the default property.

See also

GetProperty(String, BindingFlags, Binder, Type, Type[], ParameterModifier[])

使用指定的繫結條件約束搜尋指定的屬性,而該屬性的參數符合指定的引數類型和修飾詞。Searches for the specified property whose parameters match the specified argument types and modifiers, using the specified binding constraints.

public:
 virtual System::Reflection::PropertyInfo ^ GetProperty(System::String ^ name, System::Reflection::BindingFlags bindingAttr, System::Reflection::Binder ^ binder, Type ^ returnType, cli::array <Type ^> ^ types, cli::array <System::Reflection::ParameterModifier> ^ modifiers);
public System.Reflection.PropertyInfo GetProperty (string name, System.Reflection.BindingFlags bindingAttr, System.Reflection.Binder binder, Type returnType, Type[] types, System.Reflection.ParameterModifier[] modifiers);
abstract member GetProperty : string * System.Reflection.BindingFlags * System.Reflection.Binder * Type * Type[] * System.Reflection.ParameterModifier[] -> System.Reflection.PropertyInfo
override this.GetProperty : string * System.Reflection.BindingFlags * System.Reflection.Binder * Type * Type[] * System.Reflection.ParameterModifier[] -> System.Reflection.PropertyInfo
Public Function GetProperty (name As String, bindingAttr As BindingFlags, binder As Binder, returnType As Type, types As Type(), modifiers As ParameterModifier()) As PropertyInfo

Parameters

name
String

字串,包含要取得的屬性名稱。The string containing the name of the property to get.

bindingAttr
BindingFlags

列舉值的位元組合,用來指定搜尋的執行方式。A bitwise combination of the enumeration values that specify how the search is conducted.

-或--or- 要傳回 nullDefaultDefault to return null.

binder
Binder

定義一組屬性並啟用繫結的物件,可包含多載方法的選擇、引數類型的強制,以及透過反映的成員引動過程。An object that defines a set of properties and enables binding, which can involve selection of an overloaded method, coercion of argument types, and invocation of a member through reflection.

-或--or- Null 參考 (在 Visual Basic 中為 Nothing),可使用 DefaultBinderA null reference (Nothing in Visual Basic), to use the DefaultBinder.

returnType
Type

屬性的傳回類型。The return type of the property.

types
Type[]

Type 物件的陣列,代表所要取得之索引屬性的參數數目、順序和類型。An array of Type objects representing the number, order, and type of the parameters for the indexed property to get.

-或--or- 用以取得未編製索引的屬性之 Type 類型的空陣列 (也就是,Type[] types = new Type[0])。An empty array of the type Type (that is, Type[] types = new Type[0]) to get a property that is not indexed.

modifiers
ParameterModifier[]

ParameterModifier 物件的陣列,代表在 types 陣列中與對應項目關聯的屬性。An array of ParameterModifier objects representing the attributes associated with the corresponding element in the types array. 預設的繫結器不會處理這個參數。The default binder does not process this parameter.

Returns

PropertyInfo

代表符合指定之需求屬性的物件 (如有找到);否則為 nullAn object representing the property that matches the specified requirements, if found; otherwise, null.

Implements

Exceptions

找到一個以上的屬性,其具有指定名稱,且符合指定繫結條件約束。More than one property is found with the specified name and matching the specified binding constraints.

namenullname is null.

-或--or- typesnulltypes is null.

types 是多維度。types is multidimensional.

-或--or- modifiers 是多維度。modifiers is multidimensional.

-或--or- typesmodifiers 的長度不同。types and modifiers do not have the same length.

types 的項目是 nullAn element of types is null.

Remarks

如果屬性至少有一個公用存取子,則會將其視為公開給反映。A property is considered public to reflection if it has at least one accessor that is public. 否則,屬性會被視為私用,而且您必須|使用| BindingFlags.NonPublic BindingFlags.Instance BindingFlags.Static (在 Visual Basic 中,使用 Or來結合值)以取得它。Otherwise the property is considered private, and you must use BindingFlags.NonPublic | BindingFlags.Instance | BindingFlags.Static (in Visual Basic, combine the values using Or) to get it.

雖然預設的系結器不會處理 ParameterModifiermodifiers 參數),但您可以使用抽象的 System.Reflection.Binder 類別來撰寫會處理 modifiers的自訂系結器。Although the default binder does not process ParameterModifier (the modifiers parameter), you can use the abstract System.Reflection.Binder class to write a custom binder that does process modifiers. 只有在透過 COM Interop 呼叫時,才會使用 ParameterModifier,而且只會處理以傳址方式傳遞的參數。ParameterModifier is only used when calling through COM interop, and only parameters that are passed by reference are handled.

下表顯示當在類型上反映時,Get 方法傳回的基類成員。The following table shows what members of a base class are returned by the Get methods when reflecting on a type.

成員類型Member Type 靜態Static 非靜態Non-Static
建構函式Constructor No No
欄位Field No 是。Yes. 欄位一律會依名稱和簽章隱藏。A field is always hide-by-name-and-signature.
事件Event 不適用Not applicable 一般類型系統規則是,繼承與實作為屬性的方法相同。The common type system rule is that the inheritance is the same as that of the methods that implement the property. 反映會將屬性視為逐名稱和簽章。Reflection treats properties as hide-by-name-and-signature. 請參閱下面的注2。See note 2 below.
方法Method No 是。Yes. 方法(虛擬和非虛擬)可以依名稱或逐名稱和簽章來隱藏。A method (both virtual and non-virtual) can be hide-by-name or hide-by-name-and-signature.
巢狀型別Nested Type No No
屬性Property 不適用Not applicable 一般類型系統規則是,繼承與實作為屬性的方法相同。The common type system rule is that the inheritance is the same as that of the methods that implement the property. 反映會將屬性視為逐名稱和簽章。Reflection treats properties as hide-by-name-and-signature. 請參閱下面的注2。See note 2 below.
  1. [逐名稱] 和 [簽章] 會考慮簽章的所有部分,包括自訂修飾詞、傳回類型、參數類型、sentinels 和非受控呼叫慣例。Hide-by-name-and-signature considers all of the parts of the signature, including custom modifiers, return types, parameter types, sentinels, and unmanaged calling conventions. 這是二進位比較。This is a binary comparison.

  2. 針對反映,屬性和事件是依名稱和簽章來隱藏。For reflection, properties and events are hide-by-name-and-signature. 如果您在基類中具有具有 get 和 set 存取子的屬性,但衍生類別只有 get 存取子,則衍生類別屬性會隱藏基類屬性,而且您將無法存取基類上的 setter。If you have a property with both a get and a set accessor in the base class, but the derived class has only a get accessor, the derived class property hides the base class property, and you will not be able to access the setter on the base class.

  3. 自訂屬性不是一般型別系統的一部分。Custom attributes are not part of the common type system.

下列 BindingFlags 篩選旗標可以用來定義要包含在搜尋中的屬性:The following BindingFlags filter flags can be used to define which properties to include in the search:

  • 您必須指定 BindingFlags.InstanceBindingFlags.Static,才能取得傳回。You must specify either BindingFlags.Instance or BindingFlags.Static in order to get a return.

  • 指定要在搜尋中包含公用屬性 BindingFlags.PublicSpecify BindingFlags.Public to include public properties in the search.

  • 指定要在搜尋中包含非公用屬性(也就是私用、內部和受保護的屬性) BindingFlags.NonPublicSpecify BindingFlags.NonPublic to include non-public properties (that is, private, internal, and protected properties) in the search.

  • 指定 BindingFlags.FlattenHierarchy 在階層中包含 publicprotected 靜態成員;不包含繼承類別中 private 的靜態成員。Specify BindingFlags.FlattenHierarchy to include public and protected static members up the hierarchy; private static members in inherited classes are not included.

下列 BindingFlags 的修飾詞旗標可以用來變更搜尋的運作方式:The following BindingFlags modifier flags can be used to change how the search works:

  • BindingFlags.IgnoreCase 以忽略 name的大小寫。BindingFlags.IgnoreCase to ignore the case of name.

  • BindingFlags.DeclaredOnly 只搜尋 Type上宣告的屬性,而不是直接繼承的屬性。BindingFlags.DeclaredOnly to search only the properties declared on the Type, not properties that were simply inherited.

如需相關資訊,請參閱 System.Reflection.BindingFlagsSee System.Reflection.BindingFlags for more information.

如果目前的 Type 代表結構化的泛型型別,這個方法會傳回 PropertyInfo,其中的型別參數是由適當的型別引數所取代。If the current Type represents a constructed generic type, this method returns the PropertyInfo with the type parameters replaced by the appropriate type arguments.

如果目前 Type 表示泛型型別或泛型方法定義中的類型參數,這個方法會搜尋類別條件約束的屬性。If the current Type represents a type parameter in the definition of a generic type or generic method, this method searches the properties of the class constraint.

索引子和預設屬性Indexers and Default Properties

Visual Basic 2005Visual Basic 2005Visual C# 2005Visual C# 2005Visual C++ 2005Visual C++ 2005 具有存取索引屬性的簡化語法,並允許一個索引屬性作為其類型的預設值。, Visual C# 2005Visual C# 2005, and Visual C++ 2005Visual C++ 2005 have simplified syntax for accessing indexed properties and allow one indexed property to be a default for its type. 例如,如果變數 myList 參考 ArrayList,則語法 myList[3] (Visual Basic 中的myList(3))會抓取索引為3的元素。For example, if the variable myList refers to an ArrayList, the syntax myList[3] (myList(3) in Visual Basic) retrieves the element with the index of 3. 您可以多載屬性。You can overload the property.

在C#中,這項功能稱為「索引子」,而且不能依名稱參考。In C#, this feature is called an indexer and cannot be referred to by name. 根據預設, C#索引子會在中繼資料中顯示為名為 "Item" 的索引屬性。By default, a C# indexer appears in metadata as an indexed property named "Item". 不過,類別庫開發人員可以使用 IndexerNameAttribute 屬性來變更中繼資料中的索引子名稱。However, a class library developer can use the IndexerNameAttribute attribute to change the name of the indexer in the metadata. 例如,String 類別具有名為 Chars[]的索引子。For example, the String class has an indexer named Chars[]. 使用以外C#的語言建立的索引屬性,也可以有專案以外的名稱。Indexed properties created using languages other than C# can have names other than Item, as well.

若要判斷類型是否有預設屬性,請使用 GetCustomAttributes(Type, Boolean) 方法來測試 DefaultMemberAttribute 屬性。To determine whether a type has a default property, use the GetCustomAttributes(Type, Boolean) method to test for the DefaultMemberAttribute attribute. 如果類型具有 DefaultMemberAttributeMemberName 屬性會傳回預設屬性的名稱。If the type has DefaultMemberAttribute, the MemberName property returns the name of the default property.

See also

Applies to