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TreeNodeCollection.Clear Method

Removes all tree nodes from the collection.

Namespace: System.Windows.Forms
Assembly: System.Windows.Forms (in system.windows.forms.dll)

public virtual void Clear ()
public void Clear ()
public function Clear ()
Not applicable.

You can use this method to clear the entire collection of tree nodes from a tree view.

To remove an individual tree node from the collection, use the Remove or RemoveAt methods.

To add new TreeNode objects to the collection, use the Add, AddRange, or Insert methods.

The following code example copies the TreeNodeCollection from a TreeView to a temporary Array, and then adds the contents of the array to another TreeView using the AddRange method. The TreeNodeCollection from the source TreeView is cleared using the Clear method. This example requires that you have two TreeView controls, one with a collection of TreeNode objects.

private void MyButtonAddAllClick(object sender, EventArgs e)
{
   // Get the 'myTreeNodeCollection' from the 'myTreeViewBase' TreeView.
   TreeNodeCollection myTreeNodeCollection = myTreeViewBase.Nodes;
   // Create an array of 'TreeNodes'.
   TreeNode[] myTreeNodeArray = new TreeNode[myTreeViewBase.Nodes.Count];
   // Copy the tree nodes to the 'myTreeNodeArray' array.
   myTreeViewBase.Nodes.CopyTo(myTreeNodeArray,0);
   // Remove all the tree nodes from the 'myTreeViewBase' TreeView.
   myTreeViewBase.Nodes.Clear();
   // Add the 'myTreeNodeArray' to the 'myTreeViewCustom' TreeView.
   myTreeViewCustom.Nodes.AddRange(myTreeNodeArray);
}

private void myButtonAddAllClick(Object sender, EventArgs e)
{
    // Get the 'myTreeNodeCollection' from the 'myTreeViewBase' TreeView.
    TreeNodeCollection myTreeNodeCollection = myTreeViewBase.get_Nodes();
    // Create an array of 'TreeNodes'.
    TreeNode myTreeNodeArray[] =
        new TreeNode[myTreeViewBase.get_Nodes().get_Count()];
    // Copy the tree nodes to the 'myTreeNodeArray' array.
    myTreeViewBase.get_Nodes().CopyTo(myTreeNodeArray, 0);
    // Remove all the tree nodes from the 'myTreeViewBase' TreeView.
    myTreeViewBase.get_Nodes().Clear();
    // Add the 'myTreeNodeArray' to the 'myTreeViewCustom' TreeView.
    myTreeViewCustom.get_Nodes().AddRange(myTreeNodeArray);
} //myButtonAddAllClick

Windows 98, Windows Server 2000 SP4, Windows CE, Windows Millennium Edition, Windows Mobile for Pocket PC, Windows Mobile for Smartphone, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition

The Microsoft .NET Framework 3.0 is supported on Windows Vista, Microsoft Windows XP SP2, and Windows Server 2003 SP1.

.NET Framework

Supported in: 3.0, 2.0, 1.1, 1.0

.NET Compact Framework

Supported in: 2.0, 1.0
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