How to set selectedIndex of select element using display text as reference?
Example:
<input id="AnimalToFind" type="text" />
<select id="Animals">
<option value="0">Chicken</option>
<option value="1">Crocodile</option>
<option value="2">Monkey</option>
</select>
<input type="button" onclick="SelectAnimal()" />
<script type="text/javascript">
function SelectAnimal()
{
//Set selected option of Animals based on AnimalToFind value...
}
</script>
Is there any other way to do this without a loop? You know, I'm thinking of a built-in JavaScript code or something. Also, I don't use jQuery...
This question is related to
javascript
selectedindex
Try this:
function SelectAnimal()
{
var animals = document.getElementById('Animals');
var animalsToFind = document.getElementById('AnimalToFind');
// get the options length
var len = animals.options.length;
for(i = 0; i < len; i++)
{
// check the current option's text if it's the same with the input box
if (animals.options[i].innerHTML == animalsToFind.value)
{
animals.selectedIndex = i;
break;
}
}
}
You can use the HTMLOptionsCollection.namedItem() That means that you have to define your select options to have a name attribute and have the value of the displayed text. e.g California
Add name attribute to your option:
<option value="0" name="Chicken">Chicken</option>
With that you can use the HTMLOptionsCollection.namedItem("Chicken").value to set the value of your select element.
You can set the index by this code :
sel.selectedIndex = 0;
but remember a caution in this practice, You would not be able to call the server side onclick method if you select the previous value selected in the drop down..
If you want this without loops or jquery you could use the following This is straight up JavaScript. This works for current web browsers. Given the age of the question I am not sure if this would have worked back in 2011. Please note that using css style selectors is extremely powerful and can help shorten a lot of code.
// Please note that querySelectorAll will return a match for _x000D_
// for the term...if there is more than one then you will _x000D_
// have to loop through the returned object_x000D_
var selectAnimal = function() {_x000D_
var animals = document.getElementById('animal');_x000D_
if (animals) {_x000D_
var x = animals.querySelectorAll('option[value="frog"]');_x000D_
if (x.length === 1) {_x000D_
console.log(x[0].index);_x000D_
animals.selectedIndex = x[0].index;_x000D_
}_x000D_
}_x000D_
}<html>_x000D_
_x000D_
<head>_x000D_
<title>Test without loop or jquery</title>_x000D_
</head>_x000D_
_x000D_
<body>_x000D_
<label>Animal to select_x000D_
<select id='animal'>_x000D_
<option value='nothing'></option>_x000D_
<option value='dog'>dog</option>_x000D_
<option value='cat'>cat</option>_x000D_
<option value='mouse'>mouse</option>_x000D_
<option value='rat'>rat</option>_x000D_
<option value='frog'>frog</option>_x000D_
<option value='horse'>horse</option>_x000D_
</select>_x000D_
</label>_x000D_
<button onclick="selectAnimal()">Click to select animal</button>_x000D_
_x000D_
</body>_x000D_
_x000D_
</html>document.getElementById('Animal').querySelectorAll('option[value="searchterm"]'); in the index object you can now do the following: x[0].index
<script type="text/javascript">
function SelectAnimal(){
//Set selected option of Animals based on AnimalToFind value...
var animalTofind = document.getElementById('AnimalToFind');
var selection = document.getElementById('Animals');
// select element
for(var i=0;i<selection.options.length;i++){
if (selection.options[i].innerHTML == animalTofind.value) {
selection.selectedIndex = i;
break;
}
}
}
</script>
setting the selectedIndex property of the select tag will choose the correct item. it is a good idea of instead of comparing the two values (options innerHTML && animal value) you can use the indexOf() method or regular expression to select the correct option despite casing or presense of spaces
selection.options[i].innerHTML.indexOf(animalTofind.value) != -1;
or using .match(/regular expression/)
Source: Stackoverflow.com