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ConstructorNeedsTagAttribute Constructors

Definition

Initializes a new instance of the ConstructorNeedsTagAttribute class.

Overloads

ConstructorNeedsTagAttribute()

Initializes a new instance of the ConstructorNeedsTagAttribute class.

ConstructorNeedsTagAttribute(Boolean)

Initializes a new instance of the ConstructorNeedsTagAttribute class.

ConstructorNeedsTagAttribute()

Initializes a new instance of the ConstructorNeedsTagAttribute class.

public:
 ConstructorNeedsTagAttribute();
public ConstructorNeedsTagAttribute ();
Public Sub New ()

Examples

 // Attach the ConstructorNeedsTagAttribute to the custom
 // SimpleControl, which is derived from WebControl. When
 // this version of the constructor is used, the NeedsTag
 // property is automatically set to false; therefore,
 // this class does not need a tag attribute.
 [ConstructorNeedsTagAttribute()] 
 [AspNetHostingPermission(SecurityAction.Demand, 
     Level=AspNetHostingPermissionLevel.Minimal)]
 public sealed class SimpleControl : WebControl 
 {
 
      private String UserMessage=null;
 
      // Create a property named ControlValue.
      public String ControlValue 
      {
         get 
         {
            return UserMessage;
         }
         set 
         {
            UserMessage = value;
         }
       }
             
      protected override void Render(HtmlTextWriter output) 
      {
        output.Write("Testing the ConstructorNeedsTagAttribute class.");
     }
}
' Attach the ConstructorNeedsTagAttribute to the custom
' SimpleControl, which is derived from WebControl. When
' this version of the constructor is used, the NeedsTag
' property is automatically set to false; therefore,
' this class does not need a tag attribute.
<ConstructorNeedsTagAttribute()>  _
<AspNetHostingPermission(SecurityAction.Demand, _
   Level:=AspNetHostingPermissionLevel.Minimal)> _
Public NotInheritable Class SimpleControl
   Inherits WebControl
   
   Private UserMessage As [String] = Nothing
   
   ' Create a property named ControlValue.
   
   Public Property ControlValue() As [String]
      Get
         Return UserMessage
      End Get
      Set
         UserMessage = value
      End Set
   End Property
   
   
   Protected Overrides Sub Render(output As HtmlTextWriter)
      output.Write("Testing the ConstructorNeedsTagAttribute class.")
   End Sub
 End Class

See also

Applies to

ConstructorNeedsTagAttribute(Boolean)

Initializes a new instance of the ConstructorNeedsTagAttribute class.

public:
 ConstructorNeedsTagAttribute(bool needsTag);
public ConstructorNeedsTagAttribute (bool needsTag);
new System.Web.UI.ConstructorNeedsTagAttribute : bool -> System.Web.UI.ConstructorNeedsTagAttribute
Public Sub New (needsTag As Boolean)

Parameters

needsTag
Boolean

true to add a tag to a control; otherwise, false.

Examples

The following code example creates a simple custom control whose tag name is defined at run time. The following is the command line used to build the executable.

vbc /r:System.dll /r:System.Web.dll /t:library /out:myWebAppPath/Bin/vb_myconstructorNeedsTagAtt.dll constructNeedsTagAtt.vb  
csc /t:library /out:myWebAppPath/Bin/cs_myConstructorNeedsTagAtt.dll constructorNeedsTagAtt.cs  
/* File Name: constructorneedstagatt.cs. */

using System;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.ComponentModel;

namespace MyUserControl 
{
  // Attach the 'ConstructorNeedsTagAttribute' to 'Simple' class. 
  [ConstructorNeedsTagAttribute(true)]
  public class Simple : WebControl 
  {
    private String NameTag = "";

    public Simple(String tag)
    {
      this.NameTag = tag;
    } 
 
    [System.Security.Permissions.PermissionSet(System.Security.Permissions.SecurityAction.Demand, Name="FullTrust")]
    protected override void Render(HtmlTextWriter output) 
    {
      output.Write("<br>The TagName used for the 'Simple' control is "+"'"+NameTag+"'");
    }
  }  
}
' File name: constructorneedstagatt.cs. 

Imports System.Web
Imports System.Web.UI
Imports System.Web.UI.WebControls
Imports System.ComponentModel


Namespace MyUserControl
   <ConstructorNeedsTagAttribute(True)>  _
   Public Class Simple
      Inherits WebControl
      Private NameTag As [String] = ""
      
      Public Sub New(tag As [String])
        Me.NameTag = tag
      End Sub
      
      <System.Security.Permissions.PermissionSetAttribute(System.Security.Permissions.SecurityAction.Demand, Name:="FullTrust")> _
      Protected Overrides Sub Render(output As HtmlTextWriter)
        output.Write(("<br>The TagName used for the 'Simple' control is " + "'" + NameTag + "'"))
      End Sub
   End Class
End Namespace 'MyUserControl

The following code example uses the previous custom control. Notice that the values shown in the Register directive reflect the previous command line.

<%@ Register TagPrefix='MyCurrentUserControl' Namespace='MyUserControl' Assembly='vb_myConstructorNeedsTagAtt'%>  
 <html>  
  <body>  
  <form method="POST" runat="server">  
  <MyCurrentUserControl:Simple runat="server" />  
  </form>  
  </body>  
 </html>  
<%@ Register TagPrefix='MyCurrentUserControl' Namespace='MyUserControl' Assembly='cs_myConstructorNeedsTagAtt'%>  
 <html>  
  <body>  
  <form method="POST" runat="server">  
  <MyCurrentUserControl:Simple runat="server" />  
  </form>  
  </body>  
 </html>  

Applies to