Right now I wrote download code in Masterpage code behind for Menu item click. Now I want change this. When user click menu item in master page I want to call .ashx file and execute download logic. But stay in the same page where the request has made.
Please point me to right direction to implement this.
What you’re looking to do is open a new window that is pointed at the .ashx.
Here is a SO that covers that topic:
Response.Redirect to new window