Right click but disable SelectionChanged

Hello, Shubham,

SelectionChanged event triggers when the current selection has changed. On the other hand, showing the context menu is associated with a cell. That is why when using the mouse down, the cell under the cursor will get selected and then show the context menu. Thus, the SelectionChanged event is fired. 

If I understand you correctly, following the information provided in this post, you would not like to change the selection when right click with the mouse. If this is your requirement you can create a custom RadGridView and override its OnMouseDown event:

public class CustomGrid : RadGridView
{
    public override string ThemeClassName
    {
        get
        {
            return typeof(RadGridView).FullName;
        }
    }

    protected override void OnMouseDown(MouseEventArgs e)
    {
        if (e.Button == System.Windows.Forms.MouseButtons.Right)
        {
            GridCellElement cellUnderMouse = this.ElementTree.GetElementAtPoint(e.Location) as GridCellElement;
            if (cellUnderMouse != null)
            {
                this.GridViewElement.ContextMenuManager.ShowContextMenu(cellUnderMouse);
            }

            return;
        }
        base.OnMouseDown(e);
    }
}

In case this is not the exact case that you have, it would be greatly appreciated if you provide more information about the desired behavior. 

I hope this helps. Please let me know if I can assist you further.

Regards,
Nadya | Tech Support Engineer
Progress Telerik