Hello sucheendarnath,

I am assuming you are referring to WebDropDown's autofiltering functionality in this scenario. Filtering programmatically may be achieved by setting the value of the input field and invoking the filter function. Note however that this would not work if EnableAutoCompleteFirstMatch is set to true:

            function filterDD() {
                var dd = $find("WebDropDown1");
                //need to set dd input value first
                dd._elements["Input"].value = "a";
                dd.filter();
            }

Please feel free to contact me if you have any questions.

Hi,

For example, We load all continents in dropdown. Based on continents we need to apply filter for country webdropdown

We need to change the values listed in the webdropdown in the client side after binding all countries in the webdropdown server side. We need to apply filter based on continent. Is it possible to filter data based on continent in Webdropdown without postback by just filtering the datasource in javascript.

Hello sucheendarnath,

Please do not hesitate to contact me if you have any further questions regarding this matter.