protected override void OnHandleDestroyed(EventArgs e)
 {
     base.OnHandleDestroyed(e);
     this.toolTipProvider.Destroy();
     this.toolTipProvider = null;
     this.toolTipId = 0;
 }
 protected override void OnHandleCreated(EventArgs e)
 {
     base.OnHandleCreated(e);
     this.toolTipProvider = new DataGridToolTip(this);
     this.toolTipProvider.CreateToolTipHandle();
     this.toolTipId = 0;
     base.PerformLayout();
 }