Some Useful JavaScript & jQuery Snippets – Part 4

How to get client ip address with jQuery

$.getJSON("http://jsonip.appspot.com?callback=?",function(data){
    alert( "Your ip: " + data.ip);
});

How to parse XML with jQuery

file.xml:

<?xml version="1.0" ?>
<result>
    <item>
        <id>1</id>
        <title>title1</title>
        <description>desc1</description>
    </item>
    <item>
        <id>2</id>
        <title>title2</title>
        <description>desc2</description>
    </item>
    <!-- ... -->
</result>

$.get('file.xml',{},function(data){
    $('item',data).each(function(){
        var $this       = $(this);
        var id             = $this.find('id').text();
        var title         = $this.find('title').text();
        var description = $this.find('description').text();
        //do something ...
    });
});

How to get the number in the ids

<div id="sites">
    <a id="site_1" href="http://siteA.com">siteA</a>
    <a id="site_2" href="http://siteB.com">siteB</a>
    <a id="site_3" href="http://siteB.com">siteC</a>
    ...
</div>

you need to get 1 from site_1, 2 from site_2 …

$("#sites a").click(function(){
    var $this     = $(this);
    var nmb     = $this.attr('id').match(/site_(d+)/)[1];
    ...
});

How to transform a number like 12343778 into 12.343.778

<div id="result">12343778</div>

var delimiter = '.';
$('#result').html()
            .toString()
            .replace(new RegExp("(^\d{"+($this.html().toString().length%3||-1)+"})(?=\d{3})"),"$1" + delimiter)
            .replace(/(d{3})(?=d)/g,"$1" + delimiter);

Count number of textarea lines

var text = $("#textareaId").val();
var lines = text.split(/r|rn|n/);
alert(lines.length);

Logging to the firebug console

jQuery.fn.log = function (msg) {
    console.log("%s: %o", msg, this);
    return this;
};
$('#some_div').find('li.source > input:checkbox').log("sources to uncheck").removeAttr("checked");

Find X/Y of an HTML element with Javascript

// Based on: http://www.quirksmode.org/js/findpos.html
var getCumulativeOffset = function (obj) {
    var left, top;
    left = top = 0;
    if (obj.offsetParent) {
        do {
            left += obj.offsetLeft;
            top  += obj.offsetTop;
        } while (obj = obj.offsetParent);
    }
    return {
        x : left,
        y : top
    };
};

Validate Credit Card

function isCreditCard( CC ){
    if (CC.length > 19)
        return (false);

    sum = 0; mul = 1; l = CC.length;
    for (i = 0; i < l; i++){
        digit = CC.substring(l-i-1,l-i);
        tproduct = parseInt(digit ,10)*mul;
        if (tproduct >= 10)
            sum += (tproduct % 10) + 1;
        else
            sum += tproduct;
        if (mul == 1)
            mul++;
        else
            mul–;
    }
    if ((sum % 10) == 0)
        return (true);
    else
        return (false);
}

Distinguish left and right mouse click

$("#element").live('click', function(e) {
    if( (!$.browser.msie && e.button == 0) || ($.browser.msie && e.button == 1) ) {
        alert("Left Button");
    }
    else if(e.button == 2)
        alert("Right Button");
});

How to get the native image size

var img = $('#imageid');
var theImage = new Image();
theImage.src = img.attr("src");
alert("Width: " + theImage.width);
alert("Height: " + theImage.height);