How can I do a select all Check Boxes on the right click

I have a checkbox list which is coming from the database. When I just do a right click I need to display a select all and when they click on it I need to make sure that all the check boxes gets selected.
I Know how to do it if there is a check box that says select all and when the user clicks it automatically selects all the checkboxes.
But How can I just do right click and select all?? Any Ideas??
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