<!-- load jQuery 1.1.3 -->
<script type="text/javascript" src="http://example.com/jquery-1.1.3.js"></script>
<script type="text/javascript">
var jQuery_1_1_3 = $.noConflict(true);
</script>

<!-- load jQuery 1.3.2 -->
<script type="text/javascript" src="http://example.com/jquery-1.3.2.js"></script>
<script type="text/javascript">
var jQuery_1_3_2 = $.noConflict(true);
</script>

function numberWithCommas(x) {
    return x.toString().replace(/\B(?=(\d{3})+(?!\d))/g, ",");
}

function preload(arrayOfImages) {
    $(arrayOfImages).each(function(){
        $('<img/>')[0].src = this;
        // Alternatively you could use:
        // (new Image()).src = this;
    });
}

// 用法:

preload([
    'img/imageName.jpg',
    'img/anotherOne.jpg',
    'img/blahblahblah.jpg'
]);

或者使用jQuery的preload插件：

 

jQuery.isNumeric(value);

或

function isNumeric(obj) {
    return !jQuery.isArray( obj ) && (obj - parseFloat( obj ) + 1) >= 0;
}

 

if( /Android|webOS|iPhone|iPad|iPod|BlackBerry|IEMobile|Opera Mini/i.test(navigator.userAgent) ) {

// some code..

}

 

function shuffle(array) {
  var currentIndex = array.length, temporaryValue, randomIndex ;

  // While there remain elements to shuffle...
  while (0 !== currentIndex) {

    // Pick a remaining element...
    randomIndex = Math.floor(Math.random() * currentIndex);
    currentIndex -= 1;

 

$.getScript("my_lovely_script.js", function(){

   alert("Script loaded and executed.");

   // Use anything defined in the loaded script...
});

不使用jQuery的方法请参考：http://stackoverflow.com/questions/950087/include-a-javascript-file-in-another-javascript-file 

1.  YUI Compressor

2. Google Closure Compiler

3. UglifyJS

4. JSMin

以上方法只是降低代码可读性，增加破解难度，但还是不难破解的。

 

function validateEmail(email) { 
    var re = /^(([^<>()[\]\\.,;:\s@\"]+(\.[^<>()[\]\\.,;:\s@\"]+)*)|(\".+\"))@((\[[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\])|(([a-zA-Z\-0-9]+\.)+[a-zA-Z]{2,}))$/;
    return re.test(email);
}

 

// 类似于HTTP跳转

window.location.replace("http://howto.eguidedog.net");

 

// 类似于点击一个链接

window.location.href = "http://howto.eguidedog.net";