/// <summary> /// The MouseDown event of the source control is used to initiate a drag operation. /// </summary> /// <param name="sender">The source of the event.</param> /// <param name="e">A MouseEventArgs that contains the event data.</param> private void numericUpDown1_MouseDown(object sender, System.Windows.Forms.MouseEventArgs e) { // Sets a reference to the control that initiated the DragDrop operation, so // that the target control can implement logic to handle data dragged from // specific controls differently. sourceControl = numericUpDown1; // Record the mouse button that initiated this operation in order to allow // target controls to respond differently to drags with the right or left // mouse buttons. mouseButton = e.Button; // This initiates a DragDrop operation, specifying that the data to be dragged // with be the value stored in the numericUpDown1 control. This also specifies // that ONLY the Copy effect will be allowed. numericUpDown1.DoDragDrop(numericUpDown1.Value.ToString(), DragDropEffects.Copy); }