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EmptyControlCollection Class

Provides standard support for a ControlCollection collection that is always empty.

System.Object
  System.Web.UI.ControlCollection
    System.Web.UI.EmptyControlCollection

Namespace:  System.Web.UI
Assembly:  System.Web (in System.Web.dll)

public class EmptyControlCollection : ControlCollection

The EmptyControlCollection type exposes the following members.

  NameDescription
Public methodEmptyControlCollectionInitializes a new instance of the EmptyControlCollection class.
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  NameDescription
Public propertyCountGets the number of server controls in the ControlCollection object for the specified ASP.NET server control. (Inherited from ControlCollection.)
Public propertyIsReadOnlyGets a value indicating whether the ControlCollection object is read-only. (Inherited from ControlCollection.)
Public propertyIsSynchronizedGets a value indicating whether the ControlCollection object is synchronized. (Inherited from ControlCollection.)
Public propertyItemGets a reference to the server control at the specified index location in the ControlCollection object. (Inherited from ControlCollection.)
Protected propertyOwnerGets the ASP.NET server control to which the ControlCollection object belongs. (Inherited from ControlCollection.)
Public propertySyncRootGets an object that can be used to synchronize access to the collection of controls. (Inherited from ControlCollection.)
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  NameDescription
Public methodAddDenies the addition of the specified Control object to the collection. (Overrides ControlCollection.Add(Control).)
Public methodAddAtDenies the addition of the specified Control object to the collection, at the specified index position. (Overrides ControlCollection.AddAt(Int32, Control).)
Public methodClearRemoves all controls from the current server control's ControlCollection object. (Inherited from ControlCollection.)
Public methodContainsDetermines whether the specified server control is in the parent server control's ControlCollection object. (Inherited from ControlCollection.)
Public methodCopyToCopies the child controls stored in the ControlCollection object to an System.Array object, beginning at the specified index location in the System.Array. (Inherited from ControlCollection.)
Public methodEquals(Object)Determines whether the specified object is equal to the current object. (Inherited from Object.)
Protected methodFinalizeAllows an object to try to free resources and perform other cleanup operations before it is reclaimed by garbage collection. (Inherited from Object.)
Public methodGetEnumeratorRetrieves an enumerator that can iterate through the ControlCollection object. (Inherited from ControlCollection.)
Public methodGetHashCodeServes as the default hash function. (Inherited from Object.)
Public methodGetTypeGets the Type of the current instance. (Inherited from Object.)
Public methodIndexOfRetrieves the index of a specified Control object in the collection. (Inherited from ControlCollection.)
Protected methodMemberwiseCloneCreates a shallow copy of the current Object. (Inherited from Object.)
Public methodRemoveRemoves the specified server control from the parent server control's ControlCollection object. (Inherited from ControlCollection.)
Public methodRemoveAtRemoves a child control, at the specified index location, from the ControlCollection object. (Inherited from ControlCollection.)
Public methodToStringReturns a string that represents the current object. (Inherited from Object.)
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This class is used when you want to define a custom control that does not allow child controls.


/* File name: emptyControlCollection.cs. */ 

using System;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Collections;

namespace CustomControls
{

  // Defines a simple custom control. 
  public class MyCS_EmptyControl : Control
  {
    [System.Security.Permissions.PermissionSet(System.Security.Permissions.SecurityAction.Demand, Name="FullTrust")] 
    protected override ControlCollection CreateControlCollection() 
    /*
     * Function Name: CreateControlCollection.
     * Denies the creation of any child control by creating an empty collection.
     * Generates an exception if an attempt to create a child control is made.
     */
     {
       return new EmptyControlCollection(this);
     }

     [System.Security.Permissions.PermissionSet(System.Security.Permissions.SecurityAction.Demand, Name="FullTrust")] 
     protected override void CreateChildControls()
     /*
      * Function Name: CreateChildControls.
      * Populates the child control collection (Controls). 
      * Note: This function will cause an exception because the control does not allow 
      * child controls.
      */
      {
        // Create a literal control to contain the header and add it to the collection.
        LiteralControl text;
        text = new LiteralControl("<h5>Composite Controls</h5>");
        Controls.Add(text);
      }
   }

}

.NET Framework

Supported in: 4.5.2, 4.5.1, 4.5, 4, 3.5, 3.0, 2.0, 1.1, 1.0

Windows 8.1, Windows Server 2012 R2, Windows 8, Windows Server 2012, Windows 7, Windows Vista SP2, Windows Server 2008 (Server Core Role not supported), Windows Server 2008 R2 (Server Core Role supported with SP1 or later; Itanium not supported)

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.
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