selecting a char in jquery

I got a question,

<a id="shoppingLink1" href="?page=bestellen&amp;action=add&amp;i开发者_如何学JAVAd=2">
  <img src="images/shoppingcartButton.png" class="shoppingButton"  alt="shoppingcartButton" title="shoppingcartButton"/>
</a><br/>

in jquery, when i click on the shoppingButton i would like to select the last character from the id "shoppingLink". the "1" .

These are dynamicly added thou so if it comes to 10 it should automaticly select the last 2 characters. Anyone who can help me?

$('.shoppingButton').click(function () {
    var id = parseInt($(this).parent('a[id^=shoppingLink]').attr('id').match(/\d+$/)[0], 10);

    // Do stuff.

    return false;
});​

This uses RegExp to match all digits at the end of $(this).parent('a[id^=shoppingLink]').attr('id') (i.e. the .shoppingButton's parent a's id attribute where the id begins with "shoppingLink"). It then parses these digits into a number with parseInt.

Why don't you call it shopping-link-1 or something similar, and put the shoppingButton class on the a tag instead of img? That way you can use the split method to get the numeric ID. Here's some example jQuery to use:

$('a.shoppingButton').click(function() {
    var link_id = parseInt($(this).attr('id').split('-')[2]);
    // do your thing with link_id here
});

That way, when you split by the '-' character, it's guaranteed to just return the number no matter how many digits it has. But if you absolutely need to keep the current markup, use a regular expression:

$('img.shoppingButton').click(function() {
    var  link_id = parseInt($(this).parent().attr('id').match(/(\d+)$/)[1]);
    // do your thing with link_id here
});

That way it will respond to clicks on the image, and still pull the ID from the a tag.

You could look at it the other way round: you know to expect the string 'shoppingLink' so strip that off first then parse the number:

$('a.shoppingButton').click(function() {
    var theID = parseInt($(this).attr('id').replace('shoppingButton', ''));
    theID = isNaN(theID) ? 0 : theID;
    // actions here
});​