Question

How can I populate a telerik drop-down list at page load?

I get the following error(at emphasized line below) when I try to populate dropdownlist:

Error: 'data(...)' is null or not an object

Here is how I try to populate the telerik ddl:

$(function(){
var values = [];
for (var i = 1; i < 10; i++) { 

values.push({ Text: i, Value: i });
}
****$("#MyDdl").data("tDropDownList").dataBind(values);****
});

Tried it this way as well:

 $(function(){
    onDataBinding();
    });

function onDataBinding(e) {
        var MyDdl = $('#MyDdl').data('tDropDownList');
        var values = [];
        for (var i = 1; i < 10; i++) {  
    values.push({ Text: i, Value: i });
    }
      ****MyDdl.dataBind(values);****
    };

But get following undefined error at emphasized line above:

Error: 'undefined' is null or not an object

Note:
Adding a button and loading the ddl on button click event does populate telerik drop-down list.
Doing it this way works perfectly fine:

    $(function(){
   var values = [];
        for (var i = 1; i < 10; i++) {             
        values.push({ Text: i, Value: i });
        }
        $("#MyDdl").data("tDropDownList").dataBind(values);            
    });

Any help is much appreciated.

Answer 1

you need to populate it in DropDownList’s OnLoad event handler:

.ClientEvents(events => events.OnLoad("ddl_onLoad").OnChange("ddl_onChange")

handlers:

function ddl_onLoad(e) {

    var ddl = $(this).data('tDropDownList');

    ddl.dataBind([
        { Text: 'Product 1', Value: '1' },
        { Text: 'Product 2', Value: '2', Selected: true },
        { Text: 'Product 3', Value: '3' },
        { Text: 'Product 4', Value: '4' }
    ]);
}

function ddl_onChange(e) {

    //var ddl = $(this).data('tDropDownList');
    console.log(e.value);
}