如何使用javascript更改输入的样式？

Question

I want to give a

-webkit-box-shadow:inset 0 0 5px black;

property to a text box as one focuses on it.

For example, here the background-color is being changed, but I want box-shadow instead.

<script>
function myFunction(x)
{
x.style.background="yellow";
}
</script>

and the HTML

<input type="text" onfocus="myFunction(this)">

Answer 1

Why not use :focus in CSS?

http://jsfiddle.net/VjLKV/

input {
    border: 1px solid black;
}

input:focus {
    outline: none;
    border: 1px solid black;
    -webkit-box-shadow:inset 0 0 5px black;
}

Answer 2

Define css classes, and you can easily switch them as needed.

<script>
function myFunction(x)
{
x.style.className="yourcssclass";
}
</script>

Answer 3

Instead of using JS for this, use the CSS pseudo-class :focus :

input[type="text"]:focus
{
    -webkit-box-shadow:inset 0 0 5px black;
    box-shadow:inset 0 0 5px black;
}

That way, the textbox will get the shadow when the user tabs into it, or clicks it, or whatever - and the styles will properly go away when they leave, and so on.

Remember to use the unprefixed version of the box-shadow style as well.