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ControlCollection.GetEnumerator Method

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Definition

Namespace:
System.Web.UI
Assembly:
System.Web.dll

Retrieves an enumerator that can iterate through the ControlCollection object.

public:
 virtual System::Collections::IEnumerator ^ GetEnumerator();
public System.Collections.IEnumerator GetEnumerator ();
public virtual System.Collections.IEnumerator GetEnumerator ();
abstract member GetEnumerator : unit -> System.Collections.IEnumerator
override this.GetEnumerator : unit -> System.Collections.IEnumerator
Public Function GetEnumerator () As IEnumerator
Public Overridable Function GetEnumerator () As IEnumerator

Returns

IEnumerator

The enumerator to iterate through the collection.

Implements

GetEnumerator()

Examples

The following code example creates a method that enumerates through the ControlCollection collection of a Button control, myButton. When the enumerator is created, the IsSynchronized property is checked to see if the operation is thread safe, and if it is not, the SyncRoot property is used to obtain an object to make the operation thread safe. When the enumeration is completed, the value of the IsReadOnly property is written as the Text property of a Label control on the containing page.

// Create a method that enuberates through a 
// button//s ControlCollection in a thread-safe manner.  
public void ListControlCollection(object sender, EventArgs e)
{
   IEnumerator myEnumerator = myButton.Controls.GetEnumerator();

   // Check the IsSynchronized property. If False,
   // use the SyncRoot method to get an object that 
   // allows the enumeration of all controls to be 
   // thread safe.
   if (myButton.Controls.IsSynchronized == false)
   {
       lock (myButton.Controls.SyncRoot)
       {
           while (myEnumerator.MoveNext())
           {

               Object myObject = myEnumerator.Current;

               LiteralControl childControl = (LiteralControl)myEnumerator.Current;
               Response.Write("<b><br /> This is the  text of the child Control  </b>: " +
                              childControl.Text);
           }
           msgReadOnly.Text = myButton.Controls.IsReadOnly.ToString();
       }
   }       
}

' Create a method that enuberates through a 
' button's ControlCollection in a thread-safe manner.  
Public Sub ListControlCollection(sender As Object, e As EventArgs)
   Dim myEnumerator As IEnumerator = myButton.Controls.GetEnumerator()

   ' Check the IsSynchronized property. If False,
   ' use the SyncRoot method to get an object that 
   ' allows the enumeration of all controls to be 
   ' thread safe.
   If myButton.Controls.IsSynchronized = False Then
     SyncLock myButton.Controls.SyncRoot
       While (myEnumerator.MoveNext())

       Dim myObject As Object  = myEnumerator.Current
           
         Dim childControl As LiteralControl = CType(myEnumerator.Current, LiteralControl)
         Response.Write("<b><br /> This is the  text of the child Control  </b>: " & _
                        childControl.Text)
       End While
      msgReadOnly.Text = myButton.Controls.IsReadOnly.ToString()
      
      End SyncLock
   End If       
 End Sub

Applies to

See also