DesignerCategoryAttribute 類別

定義

public ref class DesignerCategoryAttribute sealed : Attribute

[System.AttributeUsage(System.AttributeTargets.Class, AllowMultiple=false, Inherited=true)]
public sealed class DesignerCategoryAttribute : Attribute

type DesignerCategoryAttribute = class
    inherit Attribute

Public NotInheritable Class DesignerCategoryAttribute
Inherits Attribute

繼承

Object

Attribute

DesignerCategoryAttribute

屬性

AttributeUsageAttribute

範例

下列範例會建立名為 MyForm的類別。The following example creates a class called MyForm. MyForm 有兩個屬性，指定此類別的 DesignerAttribute 會使用 DocumentDesigner，以及指定 Form 分類的 DesignerCategoryAttribute。MyForm has two attributes, a DesignerAttribute that specifies this class uses the DocumentDesigner, and a DesignerCategoryAttribute that specifies the Form category.

[Designer("System.Windows.Forms.Design.DocumentDesigner, System.Windows.Forms.Design",
IRootDesigner::typeid),
DesignerCategory("Form")]
ref class MyForm: public ContainerControl{
   // Insert code here.
};

[Designer("System.Windows.Forms.Design.DocumentDesigner, System.Windows.Forms.Design", 
    typeof(IRootDesigner)),
    DesignerCategory("Form")]
    
 public class MyForm : ContainerControl {
    // Insert code here.
 }

<Designer("System.Windows.Forms.Design.DocumentDesigner, System.Windows.Forms.Design", _
    GetType(IRootDesigner)), DesignerCategory("Form")> _
Public Class MyForm
    
    Inherits ContainerControl
    ' Insert code here.
End Class

下一個範例會建立 MyForm的實例。The next example creates an instance of MyForm. 然後，它會取得類別的屬性、解壓縮 DesignerCategoryAttribute，並列印設計工具的名稱。Then it gets the attributes for the class, extracts the DesignerCategoryAttribute, and prints the name of the designer.

int main()
{
   // Creates a new form.
   MyForm^ myNewForm = gcnew MyForm;

   // Gets the attributes for the collection.
   AttributeCollection^ attributes = TypeDescriptor::GetAttributes( myNewForm );

   /* Prints the name of the designer by retrieving the 
       * DesignerCategoryAttribute from the AttributeCollection. */
   DesignerCategoryAttribute^ myAttribute = dynamic_cast<DesignerCategoryAttribute^>(attributes[ DesignerCategoryAttribute::typeid ]);
   Console::WriteLine( "The category of the designer for this class is: {0}", myAttribute->Category );
   return 0;
}

public static int Main() {
    // Creates a new form.
    MyForm myNewForm = new MyForm();
 
    // Gets the attributes for the collection.
    AttributeCollection attributes = TypeDescriptor.GetAttributes(myNewForm);
 
    /* Prints the name of the designer by retrieving the 
     * DesignerCategoryAttribute from the AttributeCollection. */
    DesignerCategoryAttribute myAttribute = 
       (DesignerCategoryAttribute)attributes[typeof(DesignerCategoryAttribute)];
    Console.WriteLine("The category of the designer for this class is: " + myAttribute.Category);
  
    return 0;
}

Public Shared Function Main() As Integer
    ' Creates a new form.
    Dim myNewForm As New MyForm()
    
    ' Gets the attributes for the collection.
    Dim attributes As AttributeCollection = TypeDescriptor.GetAttributes(myNewForm)
    
    ' Prints the name of the designer by retrieving the
    ' DesignerCategoryAttribute from the AttributeCollection. 
    Dim myAttribute As DesignerCategoryAttribute = _
        CType(attributes(GetType(DesignerCategoryAttribute)), DesignerCategoryAttribute)
    Console.WriteLine(("The category of the designer for this class is: " + myAttribute.Category))
    Return 0
End Function 'Main

備註

視覺化設計工具可以使用設計工具類別，來通知將會實作為設計工具類型的開發環境。A visual designer can use a designer category to inform a development environment of the type of designer that will be implemented. 如果未在類別上提供任何設計工具類別，開發環境可能會或可能不允許設計類別。If no designer category is provided on a class, a development environment may or may not allow the class to be designed. 可以為任何名稱建立類別目錄。A category can be created for any name.

當您使用這個屬性標記類別時，它會設定為常數成員。When you mark a class with this attribute, it is set to a constant member. 當您想要在程式碼中檢查這個屬性的值時，您必須指定常數成員。When you want to check the value of this attribute in your code, you must specify the constant member. 下表中的 [描述] 資料行列出每個值設定的常數成員。The Description column in the table below lists the constant member that each value is set to.

DesignerCategoryAttribute 類別會定義下列通用分類：The DesignerCategoryAttribute class defines the following common categories:

如需詳細資訊，請參閱屬性。For more information, see Attributes.

建構函式

欄位

屬性

方法

明確介面實作

適用於

另請參閱

• Attribute
• DesignerAttribute