I have one image (img.png), with its content changing after a combo box changes.

The problem is the content of the image doesn't change when I change the combo box on the page.

I tried to use JavaScript like this:

function SwitchPic(pic) {

    pic.src = img.png;

}

and the img tag is:

<img src='img.png' id='img1' name='img1'>

and the combo box tag is:

<select name=users onchange=show(this.value);SwitchPic(img1);>

    <option value=>Select a Number:</option>

    <option value=a>a</option>

    <option value=b>b</option>

    <option value=c>c</option>

</select>

It worked the first time I change the option, but when I re-change the option, it keeps the image without changing it.

How can I solve this?