Adding a value to a dropdown through Javascript in c#

harshit verma

Hi,

I want to add a value to the Dropdownlist through Javascript but am getting Runtime Errors.

Below is my code, can some one help me on this. I tried multiple approches from webSearch but are not working.

function run() {

debugger;

var ddlvalue = document.getElementById("<%=ddlTest.ClientID%>");

if (ddlvalue.options[ddlvalue.selectedIndex].value == "0")

{

alert("Please select a value from the Dropdown!");

return;

}

var option = document.createElement('option');

option.text = 'UK';

option.value = '5';

ddlvalue.add(option); //Tried no error but value not getting added to Dropdown list.

document.getElementById("<%=ddlTest.ClientID%>").add(option);//Tried giving runtime error.

5 Replies

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Sk Imad Fakir8y ago
Jignesh Kumar8y ago
Please check below link

https://www.w3resource.com/jquery-exercises/part1/jquery-practical-exercise-31.php
Nanddeep Nachan8y ago
Please try by specifying index, where to add the option as second parameter
select.add(option, 0);
harshit verma8y ago
I am calling on button click
Nanddeep Nachan8y ago
Are you calling run() function on window.onload?
window.onload = function () {
    var select = document.getElementById("<%=ddlTest.ClientID%>");

var option = document.createElement('option');
option.text = "UK"
option.value = "5";
select.add(option, 0);
};