CodeTypeParameter CodeTypeParameter CodeTypeParameter CodeTypeParameter Class

定義

表示泛型型別或方法的型別參數。Represents a type parameter of a generic type or method.

public ref class CodeTypeParameter : System::CodeDom::CodeObject
[System.Runtime.InteropServices.ComVisible(true)]
[System.Runtime.InteropServices.ClassInterface(System.Runtime.InteropServices.ClassInterfaceType.AutoDispatch)]
[System.Serializable]
public class CodeTypeParameter : System.CodeDom.CodeObject
type CodeTypeParameter = class
    inherit CodeObject
Public Class CodeTypeParameter
Inherits CodeObject
繼承
CodeTypeParameterCodeTypeParameterCodeTypeParameterCodeTypeParameter
屬性

範例

下列程式碼範例示範如何使用CodeTypeParameter類別來建立 CodeDOM 圖形, 以產生包含泛型程式碼的應用程式。The following code example shows the use of the CodeTypeParameter class to create a CodeDOM graph to generate an application containing generics code.

using System.CodeDom;
using System.CodeDom.Compiler;
using System.Collections;
using System.Collections.Specialized;
using System.IO;
using System.Reflection;
using System.Text.RegularExpressions;
using System.Globalization;
using System.Collections.Generic;
namespace System.CodeDom
{
    class CodeDomGenericsDemo
    {
        static void Main()
        {
            try
            {
                CreateGenericsCode("cs", "Generic.cs", "GenericCS.exe");
            }
            catch (Exception e)
            {
                LogMessage("Unexpected Exception:" + e.ToString());
            }
        }

        static void CreateGenericsCode(string providerName, string sourceFileName, string assemblyName)
        {

            CodeDomProvider provider = CodeDomProvider.CreateProvider(providerName);

            LogMessage("Building CodeDOM graph...");

            CodeCompileUnit cu = new CodeCompileUnit();

            CreateGraph(provider, cu);

            StringWriter sw = new StringWriter();

            LogMessage("Generating code...");
            provider.GenerateCodeFromCompileUnit(cu, sw, null);

            string output = sw.ToString();
            output = Regex.Replace(output, "Runtime Version:[^\r\n]*",
                "Runtime Version omitted for demo");

            LogMessage("Dumping source...");
            LogMessage(output);

            LogMessage("Writing source to file...");
            Stream s = File.Open(sourceFileName, FileMode.Create);
            StreamWriter t = new StreamWriter(s);
            t.Write(output);
            t.Close();
            s.Close();

            CompilerParameters opt = new CompilerParameters(new string[]{
                                      "System.dll", 
                                      "System.Xml.dll",
                                      "System.Windows.Forms.dll",
                                      "System.Data.dll",
                                      "System.Drawing.dll"});
            opt.GenerateExecutable = false;
            opt.TreatWarningsAsErrors = true;
            opt.IncludeDebugInformation = true;
            opt.GenerateInMemory = true;

            CompilerResults results;

            LogMessage("Compiling with " + providerName);
            results = provider.CompileAssemblyFromFile(opt, sourceFileName);

            OutputResults(results);
            if (results.NativeCompilerReturnValue != 0)
            {
                LogMessage("");
                LogMessage("Compilation failed.");
            }
            else
            {
                LogMessage("");
                LogMessage("Demo completed successfully.");
            }
            File.Delete(sourceFileName);
        }

        // Create a CodeDOM graph.
        static void CreateGraph(CodeDomProvider provider, CodeCompileUnit cu)
        {
            if (!provider.Supports(GeneratorSupport.GenericTypeReference |
               GeneratorSupport.GenericTypeDeclaration))
            {
                // Return if the generator does not support generics.
                return;
            }

            CodeNamespace ns = new CodeNamespace("DemoNamespace");
            ns.Imports.Add(new CodeNamespaceImport("System"));
            ns.Imports.Add(new CodeNamespaceImport("System.Collections.Generic"));
            cu.Namespaces.Add(ns);

            // Declare a generic class.
            CodeTypeDeclaration class1 = new CodeTypeDeclaration();
            class1.Name = "MyDictionary";
            class1.BaseTypes.Add(new CodeTypeReference("Dictionary",
                                      new CodeTypeReference[] {
                                          new CodeTypeReference("TKey"),    
                                          new CodeTypeReference("TValue"),    
                                     }));
            CodeTypeParameter kType = new CodeTypeParameter("TKey");
            kType.HasConstructorConstraint = true;
            kType.Constraints.Add(new CodeTypeReference(typeof(IComparable)));
            kType.CustomAttributes.Add(new CodeAttributeDeclaration(
                "System.ComponentModel.DescriptionAttribute",
                    new CodeAttributeArgument(new CodePrimitiveExpression("KeyType"))));

            CodeTypeReference iComparableT = new CodeTypeReference("IComparable");
            iComparableT.TypeArguments.Add(new CodeTypeReference(kType));

            kType.Constraints.Add(iComparableT);

            CodeTypeParameter vType = new CodeTypeParameter("TValue");
            vType.Constraints.Add(new CodeTypeReference(typeof(IList<System.String>)));
            vType.CustomAttributes.Add(new CodeAttributeDeclaration(
                "System.ComponentModel.DescriptionAttribute",
                    new CodeAttributeArgument(new CodePrimitiveExpression("ValueType"))));

            class1.TypeParameters.Add(kType);
            class1.TypeParameters.Add(vType);

            ns.Types.Add(class1);

            // Declare a generic method.
            CodeMemberMethod printMethod = new CodeMemberMethod();
            CodeTypeParameter sType = new CodeTypeParameter("S");
            sType.HasConstructorConstraint = true;
            CodeTypeParameter tType = new CodeTypeParameter("T");
            sType.HasConstructorConstraint = true;

            printMethod.Name = "Print";
            printMethod.TypeParameters.Add(sType);
            printMethod.TypeParameters.Add(tType);

            printMethod.Statements.Add(ConsoleWriteLineStatement(
                new CodeDefaultValueExpression(new CodeTypeReference("T"))));
            printMethod.Statements.Add(ConsoleWriteLineStatement(
                new CodeDefaultValueExpression(new CodeTypeReference("S"))));

            printMethod.Attributes = MemberAttributes.Public;
            class1.Members.Add(printMethod);

            CodeTypeDeclaration class2 = new CodeTypeDeclaration();
            class2.Name = "Demo";

            CodeEntryPointMethod methodMain = new CodeEntryPointMethod();

            CodeTypeReference myClass = new CodeTypeReference(
                "MyDictionary",
                new CodeTypeReference[] {
                    new CodeTypeReference(typeof(int)),
                    new CodeTypeReference("List", 
                       new CodeTypeReference[] 
                            {new CodeTypeReference("System.String") })});

            methodMain.Statements.Add(
                  new CodeVariableDeclarationStatement(myClass,
                      "dict",
                          new CodeObjectCreateExpression(myClass)));

            methodMain.Statements.Add(ConsoleWriteLineStatement(
                new CodePropertyReferenceExpression(
                      new CodeVariableReferenceExpression("dict"),
                            "Count")));

            methodMain.Statements.Add(new CodeExpressionStatement(
                 new CodeMethodInvokeExpression(
                      new CodeMethodReferenceExpression(
                         new CodeVariableReferenceExpression("dict"),
                             "Print",
                                 new CodeTypeReference[] {
                                    new CodeTypeReference("System.Decimal"),
                                       new CodeTypeReference("System.Int32"),}),
                                           new CodeExpression[0])));

            string dictionaryTypeName = typeof(System.Collections.Generic.Dictionary<int,
                System.Collections.Generic.List<string>>[]).FullName;

            CodeTypeReference dictionaryType = new CodeTypeReference(dictionaryTypeName);
            methodMain.Statements.Add(
                  new CodeVariableDeclarationStatement(dictionaryType, "dict2",
                     new CodeArrayCreateExpression(dictionaryType, new CodeExpression[1] { new CodePrimitiveExpression(null) })));

            methodMain.Statements.Add(ConsoleWriteLineStatement(
                           new CodePropertyReferenceExpression(
                                new CodeVariableReferenceExpression("dict2"),
                                        "Length")));

            class2.Members.Add(methodMain);
            ns.Types.Add(class2);

        }

        static CodeStatement ConsoleWriteLineStatement(CodeExpression exp)
        {
            return new CodeExpressionStatement(
                new CodeMethodInvokeExpression(
                   new CodeMethodReferenceExpression(
                       new CodeTypeReferenceExpression(new CodeTypeReference("Console")),
                           "WriteLine"),
                               new CodeExpression[]{
                                   exp,
                                     }));
        }

        static CodeStatement ConsoleWriteLineStatement(string text)
        {
            return ConsoleWriteLineStatement(new CodePrimitiveExpression(text));
        }
        static void LogMessage(string text)
        {
            Console.WriteLine(text);
        }

        static void OutputResults(CompilerResults results)
        {
            LogMessage("NativeCompilerReturnValue=" +
                results.NativeCompilerReturnValue.ToString());
            foreach (string s in results.Output)
            {
                LogMessage(s);
            }
        }

    }
}
// This example generates the following code:
//------------------------------------------------------------------------------
// <auto-generated>
//     This code was generated by a tool.
//     Runtime Version omitted for demo
//
//     Changes to this file may cause incorrect behavior and will be lost if
//     the code is regenerated.
// </auto-generated>
//------------------------------------------------------------------------------

//namespace DemoNamespace
//{
//    using System;
//    using System.Collections.Generic;


//    public class MyDictionary<[System.ComponentModel.DescriptionAttribute("KeyType")]  TKey,
//          [System.ComponentModel.DescriptionAttribute("ValueType")]  TValue> : Dictionary<TKey, TValue>
//        where TKey : System.IComparable, IComparable<TKey>, new()
//        where TValue : System.Collections.Generic.IList<string>
//    {

//        public virtual void Print<S, T>()
//            where S : new()
//        {
//            Console.WriteLine(default(T));
//            Console.WriteLine(default(S));
//        }
//    }

//    public class Demo
//    {

//        public static void Main()
//        {
//            MyDictionary<int, List<string>> dict = new MyDictionary<int, List<string>>();
//            Console.WriteLine(dict.Count);
//            dict.Print<decimal, int>();
//            System.Collections.Generic.Dictionary<int, System.Collections.Generic.List<string>>[] dict2 =
//              new System.Collections.Generic.Dictionary<int, System.Collections.Generic.List<string>>[] { null };
//            Console.WriteLine(dict2.Length);
//        }
//    }
//}

Imports System.CodeDom
Imports System.CodeDom.Compiler
Imports System.Collections
Imports System.Collections.Specialized
Imports System.IO
Imports System.Reflection
Imports System.Text.RegularExpressions
Imports System.Globalization
Imports System.Collections.Generic


Class CodeDomGenericsDemo

    Shared Sub Main()
        Try
            CreateGenericsCode("vb", "Generic.vb", "GenericVB.exe")
        Catch e As Exception
            LogMessage(("Unexpected Exception:" + e.ToString()))
        End Try

    End Sub


    Shared Sub CreateGenericsCode(ByVal providerName As String, ByVal sourceFileName As String, ByVal assemblyName As String)

        Dim provider As CodeDomProvider = CodeDomProvider.CreateProvider(providerName)

        LogMessage("Building CodeDOM graph...")

        Dim cu As New CodeCompileUnit()

        CreateGraph(provider, cu)

        Dim sw As New StringWriter()

        LogMessage("Generating code...")
        provider.GenerateCodeFromCompileUnit(cu, sw, Nothing)

        Dim output As String = sw.ToString()
        output = Regex.Replace(output, "Runtime version:[^" + vbCr + vbLf + "]*", "Runtime version omitted for demo")

        LogMessage("Displaying source code...")
        LogMessage(output)

        LogMessage("Writing source code to file...")
        Dim s As Stream = File.Open(sourceFileName, FileMode.Create)
        Dim t As New StreamWriter(s)
        t.Write(output)
        t.Close()
        s.Close()

        Dim opt As New CompilerParameters(New String() {"System.dll", "System.Xml.dll", "System.Windows.Forms.dll", "System.Data.dll", "System.Drawing.dll"})
        opt.GenerateExecutable = False
        opt.TreatWarningsAsErrors = True
        opt.IncludeDebugInformation = True
        opt.GenerateInMemory = True

        Dim results As CompilerResults

        LogMessage(("Compiling with provider " + providerName))
        results = provider.CompileAssemblyFromFile(opt, sourceFileName)

        OutputResults(results)
        If results.NativeCompilerReturnValue <> 0 Then
            LogMessage("")
            LogMessage("Compilation failed.")
        Else
            LogMessage("")
            LogMessage("Demo completed successfully.")
        End If
        File.Delete(sourceFileName)

    End Sub


    ' Create a CodeDOM graph.
    Shared Sub CreateGraph(ByVal provider As CodeDomProvider, ByVal cu As CodeCompileUnit)
        ' Determine if the generator supports generics.
        If Not provider.Supports(GeneratorSupport.GenericTypeReference Or GeneratorSupport.GenericTypeDeclaration) Then
            ' Return if the generator does not support generics.
            Return
        End If
        Dim ns As New CodeNamespace("DemoNamespace")
        ns.Imports.Add(New CodeNamespaceImport("System"))
        ns.Imports.Add(New CodeNamespaceImport("System.Collections.Generic"))
        cu.Namespaces.Add(ns)

        ' Declare a generic class.
        Dim class1 As New CodeTypeDeclaration()
        class1.Name = "MyDictionary"
        class1.BaseTypes.Add( _
            New CodeTypeReference("Dictionary", _
                New CodeTypeReference() {New CodeTypeReference("TKey"), _
                    New CodeTypeReference("TValue")}))
        Dim kType As New CodeTypeParameter("TKey")
        kType.HasConstructorConstraint = True
        kType.Constraints.Add(New CodeTypeReference(GetType(IComparable)))
        kType.CustomAttributes.Add _
            (New CodeAttributeDeclaration("System.ComponentModel.DescriptionAttribute", _
                New CodeAttributeArgument(New CodePrimitiveExpression("KeyType"))))
        Dim iComparableT As New CodeTypeReference("IComparable")
        iComparableT.TypeArguments.Add(New CodeTypeReference(kType))

        kType.Constraints.Add(iComparableT)

        Dim vType As New CodeTypeParameter("TValue")
        vType.Constraints.Add(New CodeTypeReference(GetType(IList(Of System.String))))
        vType.CustomAttributes.Add _
            (New CodeAttributeDeclaration("System.ComponentModel.DescriptionAttribute", _
                New CodeAttributeArgument(New CodePrimitiveExpression("ValueType"))))

        class1.TypeParameters.Add(kType)
        class1.TypeParameters.Add(vType)
        ns.Types.Add(class1)

        ' Declare a generic method.
        Dim printMethod As New CodeMemberMethod()
        Dim sType As New CodeTypeParameter("S")
        sType.HasConstructorConstraint = True
        Dim tType As New CodeTypeParameter("T")
        tType.HasConstructorConstraint = True

        printMethod.Name = "Print"
        printMethod.TypeParameters.Add(sType)
        printMethod.TypeParameters.Add(tType)

        printMethod.Statements.Add(ConsoleWriteLineStatement _
            (New CodeDefaultValueExpression(New CodeTypeReference("T"))))
        printMethod.Statements.Add(ConsoleWriteLineStatement _
            (New CodeDefaultValueExpression(New CodeTypeReference("S"))))
        printMethod.Attributes = MemberAttributes.Public
        class1.Members.Add(printMethod)

        Dim class2 As New CodeTypeDeclaration()
        class2.Name = "Demo"

        Dim methodMain As New CodeEntryPointMethod()

        Dim [myClass] As New CodeTypeReference("MyDictionary", _
            New CodeTypeReference() {New CodeTypeReference(GetType(Integer)), _
                New CodeTypeReference("List", _
                    New CodeTypeReference() {New CodeTypeReference("System.String")})})

        methodMain.Statements.Add(New CodeVariableDeclarationStatement([myClass], _
            "dict", New CodeObjectCreateExpression([myClass])))

        methodMain.Statements.Add(ConsoleWriteLineStatement _
            (New CodePropertyReferenceExpression _
                (New CodeVariableReferenceExpression("dict"), "Count")))

        methodMain.Statements.Add _
            (New CodeExpressionStatement _
                (New CodeMethodInvokeExpression _
                    (New CodeMethodReferenceExpression _
                        (New CodeVariableReferenceExpression("dict"), _
                            "Print", New CodeTypeReference() _
                                    {New CodeTypeReference("System.Decimal"), _
                                        New CodeTypeReference("System.Int32")}), _
                                            New CodeExpression(-1) {})))
        Dim longTypeName As String = GetType( _
            System.Collections.Generic.Dictionary(Of Integer, _
                System.Collections.Generic.List(Of String))()).FullName

        Dim longType As New CodeTypeReference(longTypeName)

        methodMain.Statements.Add(New CodeVariableDeclarationStatement _
            (longType, "dict2", New CodeArrayCreateExpression _
                (longType, New CodeExpression(0) {New CodePrimitiveExpression(Nothing)})))

        methodMain.Statements.Add(ConsoleWriteLineStatement(New CodePropertyReferenceExpression(New CodeVariableReferenceExpression("dict2"), "Length")))

        class2.Members.Add(methodMain)
        ns.Types.Add(class2)

    End Sub


    Overloads Shared Function ConsoleWriteLineStatement(ByVal exp As CodeExpression) As CodeStatement
        Return New CodeExpressionStatement(New CodeMethodInvokeExpression _
            (New CodeMethodReferenceExpression _
                (New CodeTypeReferenceExpression _
                    (New CodeTypeReference("Console")), "WriteLine"), _
                        New CodeExpression() {exp}))

    End Function 'ConsoleWriteLineStatement


    Overloads Shared Function ConsoleWriteLineStatement(ByVal [text] As String) As CodeStatement
        Return ConsoleWriteLineStatement(New CodePrimitiveExpression([text]))

    End Function 'ConsoleWriteLineStatement

    Shared Sub LogMessage(ByVal [text] As String)
        Console.WriteLine([text])

    End Sub


    Shared Sub OutputResults(ByVal results As CompilerResults)
        LogMessage(("NativeCompilerReturnValue=" + results.NativeCompilerReturnValue.ToString()))
        Dim s As String
        For Each s In results.Output
            LogMessage(s)
        Next s

    End Sub
End Class
'
' This example generates the following code:
'------------------------------------------------------------------------------
' <auto-generated>
'     This code was generated by a tool.
'     Runtime Version:2.0.50727.1434
'
'     Changes to this file may cause incorrect behavior and will be lost if
'     the code is regenerated.
' </auto-generated>
'------------------------------------------------------------------------------

'Option Strict Off
'Option Explicit On

''Imports System.Collections.Generic

'Namespace DemoNamespace

'    Public Class MyDictionary(Of TKey As  {System.IComparable, IComparable(Of TKey), New}, TValue As System.Collections.
'Generic.IList(Of String))
'        Inherits Dictionary(Of TKey, TValue)

'        Public Overridable Sub Print(Of S As New, T As New)()
'            Console.WriteLine(CType(Nothing, T))
'            Console.WriteLine(CType(Nothing, S))
'        End Sub
'    End Class

'    Public Class Demo

'        Public Shared Sub Main()
'            Dim dict As MyDictionary(Of Integer, List(Of String)) = New MyDictionary(Of Integer, List(Of String))
'            Console.WriteLine(dict.Count)
'            dict.Print(Of Decimal, Integer)()
'            Dim dict2() As System.Collections.Generic.Dictionary(Of Integer, System.Collections.Generic.List(Of String))
' = New System.Collections.Generic.Dictionary(Of Integer, System.Collections.Generic.List(Of String))() {Nothing}
'            Console.WriteLine(dict2.Length)
'        End Sub
'    End Class
'End Namespace

備註

CodeTypeParameter類別代表泛型型別或方法宣告中的型別參數。The CodeTypeParameter class represents a type parameter in the declaration of a generic type or method.

泛型型別或方法宣告包含一或多個未指定的類型, 稱為類型參數。A generic type or method declaration contains one or more unspecified types known as type parameters. 類型參數名稱代表泛型宣告主體內的類型。A type parameter name stands for the type within the body of the generic declaration. 例如, List<T>類別的泛型宣告包含型別參數TFor example, the generic declaration for the List<T> class contains the type parameter T.

如需泛型的詳細資訊, 請參閱.NET Framework 類別庫中的泛型For more information on generics, see Generics in the .NET Framework Class Library.

建構函式

CodeTypeParameter() CodeTypeParameter() CodeTypeParameter() CodeTypeParameter()

初始化 CodeTypeParameter 類別的新執行個體。Initializes a new instance of the CodeTypeParameter class.

CodeTypeParameter(String) CodeTypeParameter(String) CodeTypeParameter(String) CodeTypeParameter(String)

使用指定的型別參數名稱,初始化 CodeTypeParameter 類別的新執行個體。Initializes a new instance of the CodeTypeParameter class with the specified type parameter name.

屬性

Constraints Constraints Constraints Constraints

取得型別參數的條件約束。Gets the constraints for the type parameter.

CustomAttributes CustomAttributes CustomAttributes CustomAttributes

取得型別參數的自訂屬性。Gets the custom attributes of the type parameter.

HasConstructorConstraint HasConstructorConstraint HasConstructorConstraint HasConstructorConstraint

取得或設定值,指出型別參數是否具有建構函式條件約束。Gets or sets a value indicating whether the type parameter has a constructor constraint.

Name Name Name Name

取得或設定型別參數的名稱。Gets or sets the name of the type parameter.

UserData UserData UserData UserData

取得目前物件的使用者可定義資料。Gets the user-definable data for the current object.

(Inherited from CodeObject)

方法

Equals(Object) Equals(Object) Equals(Object) Equals(Object)

判斷指定的物件是否等於目前的物件。Determines whether the specified object is equal to the current object.

(Inherited from Object)
GetHashCode() GetHashCode() GetHashCode() GetHashCode()

做為預設雜湊函式。Serves as the default hash function.

(Inherited from Object)
GetType() GetType() GetType() GetType()

取得目前執行個體的 TypeGets the Type of the current instance.

(Inherited from Object)
MemberwiseClone() MemberwiseClone() MemberwiseClone() MemberwiseClone()

建立目前 Object 的淺層複本 (Shallow Copy)。Creates a shallow copy of the current Object.

(Inherited from Object)
ToString() ToString() ToString() ToString()

傳回代表目前物件的字串。Returns a string that represents the current object.

(Inherited from Object)

適用於