How To Set Default Value For Html Select?

I have a HTML select like this: abc and I hav

Solution 1:

You first need to add values to your select options and for easy targetting give the select itself an id.

Let's make option b the default:

<selectid="mySelect"><option>a</option><optionselected="selected">b</option><option>c</option></select>

Now you can change the default selected value with JavaScript like this:

<script>var temp = "a";
var mySelect = document.getElementById('mySelect');

for(var i, j = 0; i = mySelect.options[j]; j++) {
    if(i.value == temp) {
        mySelect.selectedIndex = j;
        break;
    }
}
</script>

Also we can use "text" property of i to validate:

if(i.text == temp)

See it in action on codepen.

Solution 2:

Note: this is JQuery. See Sébastien answer for Javascript

$(function() {
    var temp="a"; 
    $("#MySelect").val(temp);
});

<selectname="MySelect"id="MySelect"><optionvalue="a">a</option><optionvalue="b">b</option><optionvalue="c">c</option></select>

Solution 3:

You should define the attributes of option like selected="selected"

<select><optionselected="selected">a</option><option>b</option><option>c</option></select>

Solution 4:

Simplay you can place HTML select attribute to option a like shown below

Define the attributes like selected="selected"

<select><optionselected="selected">a</option><option>b</option><option>c</option></select>

Solution 5:

you can define attribute selected="selected" in Ex a