TreeView.LabelEdit TreeView.LabelEdit TreeView.LabelEdit TreeView.LabelEdit Property

Definición

Obtiene o establece un valor que indica si el texto de las etiquetas de los nodos de árbol se puede editar.Gets or sets a value indicating whether the label text of the tree nodes can be edited.

public:
 property bool LabelEdit { bool get(); void set(bool value); };
public bool LabelEdit { get; set; }
member this.LabelEdit : bool with get, set
Public Property LabelEdit As Boolean

Valor de propiedad

Es true si se puede editar el texto de las etiquetas de los nodos de árbol; en caso contrario, es false.true if the label text of the tree nodes can be edited; otherwise, false. De manera predeterminada, es false.The default is false.

Ejemplos

El ejemplo de código siguiente permite al usuario modificar los nodos de nodos de árbol mediante el uso de un ContextMenu.The following code example lets the user edit nonroot tree nodes by using a ContextMenu. Cuando el usuario hace clic con el mouse, el TreeNode de dicha posición determina y almacenan en una variable denominada mySelectedNode.When the user right clicks the mouse, the TreeNode at that position is determined and stored in a variable named mySelectedNode. Si se ha seleccionado un nodo de árbol sin raíz, se coloca en un estado modificable, lo que permite al usuario editar la etiqueta del nodo.If a nonroot tree node was selected, it is put into an editable state, which allows the user to edit the node label. Después de que el usuario termina de editar la etiqueta del nodo de árbol, se evalúa y se guarda el nuevo texto de etiqueta.After the user stops editing the tree node label, the new label text is evaluated and saved. En este ejemplo, varios caracteres se consideran no válidos en el texto de etiqueta.For this example, several characters are considered not valid in the label text. Si uno de los caracteres no válidos se encuentra en la cadena de la etiqueta o la cadena está vacía, se notifica al usuario del error y la etiqueta se devuelve el texto anterior.If one of the invalid characters is in the label string, or the string is empty, the user is notified of the error and the label is returned to its previous text.

   /* Get the tree node under the mouse pointer and 
      save it in the mySelectedNode variable. */
private:
   void treeView1_MouseDown( Object^ /*sender*/, System::Windows::Forms::MouseEventArgs^ e )
   {
      mySelectedNode = treeView1->GetNodeAt( e->X, e->Y );
   }

   void menuItem1_Click( Object^ /*sender*/, System::EventArgs^ /*e*/ )
   {
      if ( mySelectedNode != nullptr && mySelectedNode->Parent != nullptr )
      {
         treeView1->SelectedNode = mySelectedNode;
         treeView1->LabelEdit = true;
         if (  !mySelectedNode->IsEditing )
         {
            mySelectedNode->BeginEdit();
         }
      }
      else
      {
         MessageBox::Show( String::Concat( "No tree node selected or selected node is a root node.\n",
            "Editing of root nodes is not allowed." ), "Invalid selection" );
      }
   }

   void treeView1_AfterLabelEdit( Object^ /*sender*/,
      System::Windows::Forms::NodeLabelEditEventArgs^ e )
   {
      if ( e->Label != nullptr )
      {
         if ( e->Label->Length > 0 )
         {
            array<Char>^ temp0 = {'@','.',',','!'};
            if ( e->Label->IndexOfAny( temp0 ) == -1 )
            {
               
               // Stop editing without canceling the label change.
               e->Node->EndEdit( false );
            }
            else
            {
               /* Cancel the label edit action, inform the user, and 
                  place the node in edit mode again. */
               e->CancelEdit = true;
               MessageBox::Show( String::Concat( "Invalid tree node label.\n",
                  "The invalid characters are: '@','.', ',', '!'" ),
                  "Node Label Edit" );
               e->Node->BeginEdit();
            }
         }
         else
         {
            /* Cancel the label edit action, inform the user, and 
               place the node in edit mode again. */
            e->CancelEdit = true;
            MessageBox::Show( "Invalid tree node label.\nThe label cannot be blank",
               "Node Label Edit" );
            e->Node->BeginEdit();
         }
      }
   }
/* Get the tree node under the mouse pointer and 
   save it in the mySelectedNode variable. */
private void treeView1_MouseDown(object sender, 
  System.Windows.Forms.MouseEventArgs e)
{
   mySelectedNode = treeView1.GetNodeAt(e.X, e.Y);
}

private void menuItem1_Click(object sender, System.EventArgs e)
{
   if (mySelectedNode != null && mySelectedNode.Parent != null)
   {
      treeView1.SelectedNode = mySelectedNode;
      treeView1.LabelEdit = true;
      if(!mySelectedNode.IsEditing)
      {
         mySelectedNode.BeginEdit();
      }
   }
   else
   {
      MessageBox.Show("No tree node selected or selected node is a root node.\n" + 
         "Editing of root nodes is not allowed.", "Invalid selection");
   }
}

private void treeView1_AfterLabelEdit(object sender, 
         System.Windows.Forms.NodeLabelEditEventArgs e)
{
   if (e.Label != null)
   {
     if(e.Label.Length > 0)
     {
        if (e.Label.IndexOfAny(new char[]{'@', '.', ',', '!'}) == -1)
        {
           // Stop editing without canceling the label change.
           e.Node.EndEdit(false);
        }
        else
        {
           /* Cancel the label edit action, inform the user, and 
              place the node in edit mode again. */
           e.CancelEdit = true;
           MessageBox.Show("Invalid tree node label.\n" + 
              "The invalid characters are: '@','.', ',', '!'", 
              "Node Label Edit");
           e.Node.BeginEdit();
        }
     }
     else
     {
        /* Cancel the label edit action, inform the user, and 
           place the node in edit mode again. */
        e.CancelEdit = true;
        MessageBox.Show("Invalid tree node label.\nThe label cannot be blank", 
           "Node Label Edit");
        e.Node.BeginEdit();
     }
   }
}
' Get the tree node under the mouse pointer and
' save it in the mySelectedNode variable. 
Private Sub treeView1_MouseDown(sender As Object, _
  e As System.Windows.Forms.MouseEventArgs)
        
   mySelectedNode = treeView1.GetNodeAt(e.X, e.Y)
End Sub    
    
Private Sub menuItem1_Click(sender As Object, e As System.EventArgs)
   If Not (mySelectedNode Is Nothing) And _
     Not (mySelectedNode.Parent Is Nothing) Then
      treeView1.SelectedNode = mySelectedNode
      treeView1.LabelEdit = True
      If Not mySelectedNode.IsEditing Then
         mySelectedNode.BeginEdit()
      End If
   Else
      MessageBox.Show("No tree node selected or selected node is a root node." & _
        Microsoft.VisualBasic.ControlChars.Cr & _
        "Editing of root nodes is not allowed.", "Invalid selection")
   End If
End Sub    
    
Private Sub treeView1_AfterLabelEdit(sender As Object, _
  e As System.Windows.Forms.NodeLabelEditEventArgs)
   If Not (e.Label Is Nothing) Then
      If e.Label.Length > 0 Then
         If e.Label.IndexOfAny(New Char() {"@"c, "."c, ","c, "!"c}) = -1 Then
            ' Stop editing without canceling the label change.
            e.Node.EndEdit(False)
         Else
            ' Cancel the label edit action, inform the user, and
            ' place the node in edit mode again. 
            e.CancelEdit = True
            MessageBox.Show("Invalid tree node label." & _
              Microsoft.VisualBasic.ControlChars.Cr & _
              "The invalid characters are: '@','.', ',', '!'", _
              "Node Label Edit")
            e.Node.BeginEdit()
         End If
      Else
         ' Cancel the label edit action, inform the user, and
         ' place the node in edit mode again. 
         e.CancelEdit = True
         MessageBox.Show("Invalid tree node label." & _
           Microsoft.VisualBasic.ControlChars.Cr & _
           "The label cannot be blank", "Node Label Edit")
           e.Node.BeginEdit()
      End If
   End If
End Sub 

Comentarios

El BeginEdit método sólo funciona si la LabelEdit propiedad es true.The BeginEdit method works only if the LabelEdit property is true. Si LabelEdit es false al intentar editar la etiqueta, se producirá una excepción y el nodo de árbol no se pondrán en estado editable.If LabelEdit is false when you attempt to edit the label, an exception will be thrown and the tree node will not be put in to an editable state.

Se aplica a

Consulte también: