TreeView.AfterCheck TreeView.AfterCheck TreeView.AfterCheck TreeView.AfterCheck Event

정의

트리 노드 확인란이 선택된 후에 발생합니다.Occurs after the tree node check box is checked.

public:
 event System::Windows::Forms::TreeViewEventHandler ^ AfterCheck;
public event System.Windows.Forms.TreeViewEventHandler AfterCheck;
member this.AfterCheck : System.Windows.Forms.TreeViewEventHandler 
Public Custom Event AfterCheck As TreeViewEventHandler 

예제

모든 자식 트리 노드를 업데이트 하는 다음 코드 예제는 TreeNode 사용자의 선택된 상태를 변경 하는 경우.The following code example updates all the child tree nodes of a TreeNode when the user changes its checked state. 이 코드를 실행 하려면를 Form 사용 하 여는 TreeViewTreeNode 개체에 해당 TreeNodeCollection합니다.This code requires that you have a Form with a TreeView that has TreeNode objects in its TreeNodeCollection. TreeNodeCollection 트리 노드가 자식 노드와 함께 있어야 합니다.The TreeNodeCollection should have tree nodes with child nodes.

// Updates all child tree nodes recursively.
void CheckAllChildNodes( TreeNode^ treeNode, bool nodeChecked )
{
   IEnumerator^ myEnum = treeNode->Nodes->GetEnumerator();
   while ( myEnum->MoveNext() )
   {
      TreeNode^ node = safe_cast<TreeNode^>(myEnum->Current);
      node->Checked = nodeChecked;
      if ( node->Nodes->Count > 0 )
      {
         
         // If the current node has child nodes, call the CheckAllChildsNodes method recursively.
         this->CheckAllChildNodes( node, nodeChecked );
      }
   }
}

// NOTE   This code can be added to the BeforeCheck event handler instead of the AfterCheck event.
// After a tree node's Checked property is changed, all its child nodes are updated to the same value.
void node_AfterCheck( Object^ /*sender*/, TreeViewEventArgs^ e )
{
   // The code only executes if the user caused the checked state to change.
   if ( e->Action != TreeViewAction::Unknown )
   {
      if ( e->Node->Nodes->Count > 0 )
      {
         /* Calls the CheckAllChildNodes method, passing in the current
             Checked value of the TreeNode whose checked state changed. */
         this->CheckAllChildNodes( e->Node, e->Node->Checked );
      }
   }
}
// Updates all child tree nodes recursively.
private void CheckAllChildNodes(TreeNode treeNode, bool nodeChecked)
{
   foreach(TreeNode node in treeNode.Nodes)
   {
      node.Checked = nodeChecked;
      if(node.Nodes.Count > 0)
      {
         // If the current node has child nodes, call the CheckAllChildsNodes method recursively.
         this.CheckAllChildNodes(node, nodeChecked);
      }
   }
}

// NOTE   This code can be added to the BeforeCheck event handler instead of the AfterCheck event.
// After a tree node's Checked property is changed, all its child nodes are updated to the same value.
private void node_AfterCheck(object sender, TreeViewEventArgs e)
{
   // The code only executes if the user caused the checked state to change.
   if(e.Action != TreeViewAction.Unknown)
   {
      if(e.Node.Nodes.Count > 0)
      {
         /* Calls the CheckAllChildNodes method, passing in the current 
         Checked value of the TreeNode whose checked state changed. */
         this.CheckAllChildNodes(e.Node, e.Node.Checked);
      }
   }
}
' Updates all child tree nodes recursively.
Private Sub CheckAllChildNodes(treeNode As TreeNode, nodeChecked As Boolean)
   Dim node As TreeNode
   For Each node In  treeNode.Nodes 
      node.Checked = nodeChecked
      If node.Nodes.Count > 0 Then
         ' If the current node has child nodes, call the CheckAllChildsNodes method recursively.
         Me.CheckAllChildNodes(node, nodeChecked)
      End If
   Next node
End Sub
      
' NOTE   This code can be added to the BeforeCheck event handler instead of the AfterCheck event.
' After a tree node's Checked property is changed, all its child nodes are updated to the same value.
Private Sub node_AfterCheck(sender As Object, e As TreeViewEventArgs) Handles treeView1.AfterCheck
   ' The code only executes if the user caused the checked state to change.
   If e.Action <> TreeViewAction.Unknown Then 
      If e.Node.Nodes.Count > 0 Then
         ' Calls the CheckAllChildNodes method, passing in the current 
         ' Checked value of the TreeNode whose checked state changed. 
         Me.CheckAllChildNodes(e.Node, e.Node.Checked)
      End If
   End If
End Sub 

설명

설정 된 TreeNode.Checked 내에서 속성을 BeforeCheck 또는 AfterCheck 이벤트 처리기는 이벤트를 여러 번 발생 시키고 예기치 않은 동작이 발생할 수 있습니다.Setting the TreeNode.Checked property from within a BeforeCheck or AfterCheck event handler causes the event to be raised multiple times and can result in unexpected behavior. 이벤트가 여러 번 발생을 방지 하려면 논리만 경우 재귀 코드를 실행 하는 이벤트 처리기를 추가 합니다는 Action 의 속성을 TreeViewEventArgs 로 설정 되지 않은 TreeViewAction.Unknown.To prevent the event from being raised multiple times, add logic to your event handler that only executes your recursive code if the Action property of the TreeViewEventArgs is not set to TreeViewAction.Unknown.

이벤트 처리에 대한 자세한 내용은 이벤트 처리 및 발생 을 참조하십시오.For more information about handling events, see Handling and Raising Events.

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