ListBox.EndUpdate Method ()


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Resumes painting the ListBox control after painting is suspended by the BeginUpdate method.

Namespace:   System.Windows.Forms
Assembly:  System.Windows.Forms (in System.Windows.Forms.dll)

public void EndUpdate()

The preferred way to add items to the ListBox is to use the AddRange method of the ListBox.ObjectCollection class (through the Items property of the ListBox). This enables you to add an array of items to the list at one time. However, if you want to add items one at a time using the Add method of the ListBox.ObjectCollection class, you can use the BeginUpdate method to prevent the control from repainting the ListBox each time an item is added to the list. Once you have completed the task of adding items to the list, call the EndUpdate method to enable the ListBox to repaint. This way of adding items can prevent flickered drawing of the ListBox when a large number of items are being added to the list.

The following code example uses the BeginUpdate and EndUpdate methods while adding five thousand items to a ListBox. This example requires that a ListBox control, named listBox1, has been added to a Form and that this method is placed within the form and called from it.

public void AddToMyListBox()
   // Stop the ListBox from drawing while items are added.

   // Loop through and add five thousand new items.
   for(int x = 1; x < 5000; x++)
      listBox1.Items.Add("Item " + x.ToString());   
   // End the update process and force a repaint of the ListBox.

.NET Framework
Available since 1.1
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