Question

the jquery work perfectly when I use the snippets in .aspx including this

$(function() {
    var availableTags = [
        "ActionScript",
        "AppleScript",
        "Asp",
        "BASIC",
        "C",
        "C++"
    ];
    $( "#tags" ).autocomplete({
        source: availableTags
    });
});
</script>

then I wrote following code in my .cs file

 protected void Page_Load(object sender, EventArgs e)
{

    DataClassesDataContext db = new DataClassesDataContext();
    var val = from q in db.ques_tbls select q.qTitle;
    db.SubmitChanges();
}

after adding this I changed one line in the script in .aspx like this

 var availableTags = <%=val%>;

I ended up with this error.
.
Compiler Error Message: CS0103: The name ‘val’ does not exist in the current context

Source Error:

Line 12:       <script type="text/javascript">
Line 13:           $(function () {
Line 14:               var availableTags = <%=val %>;
Line 15:               function split(val) {
Line 16:                   return val.split(/,\s*/);

Answer 1

You declared val a local variable to your Page_Load method

   var val = from q in db.ques_tbls select q.qTitle; 

It must exist at the class level for the aspx page to use it. Create a member or property to store the value.