[jQuery] line breaks are removed when posting data in ajax

[xhe]

I was using jquery to post data to backend php code using ajax.

 $.post("<?php echo url_for("saveadmincmt")?>", { rptID: val, cmt: $
("#adminCmt"+val).val()},function(data){
           if(data=="done"){
                alert ("Admin comment has been succesfully saved.");
                $("#divadmincmtcontent"+val).html($
("#adminCmt"+val).val());
            }
       });

See here the cmt, when I submit the request, all the line break have
been removed. So that means originally text area link breaks no longer
exist, instead it become a long sentence.

So how can I keep the original line break when sending the request to
backend?

Thanks