Hi 
The below code is  working fine if the user didnt enter to his account then he click on the button he will get this message:"Please login to add this Ads to your favorite list" and if he already enter to his account then he will get this message: "  This Ads has been added to your favorite list ", but what i am looking for is not to duplicate the record in the table of the ads so user can added once and if he delete then he can added again. so if the ads already stored in the favoritetable under the same user then a message will appear : " you have already added this ads to your favorite list before".

protected void likebtn_Click(object sender, ImageClickEventArgs e) { if (Session["UsrNme"] != null) { var user = Session["UsrNme"]; using (var likeCon = new SqlC ...

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