动态加载jQuery

Question

我在使用Javascript加载jQuery时遇到了问题。我需要用Javascript加载它，因为有一些情况我只能在客户端知道。被注释掉的代码应该是用来初始化脚本的，但我对它们一无所知。

var script_tag = document.createElement('script');
script_tag.setAttribute("type","text/javascript");
script_tag.setAttribute("src","http://ajax.googleapis.com/ajax/libs/jquery/1.4.2/jquery.min.js")
//script_tag.onload = main; // Run main() once jQuery has loaded
//script_tag.onreadystatechange = function () { // Same thing but for IE
    //if (this.readyState == 'complete' || this.readyState == 'loaded') main();
//}
document.getElementsByTagName("head")[0].appendChild(script_tag);

http://mybsabusiness.com/samplesites/silver/sbsa01/

这就是问题所在的网站。

Answer 1

在jQuerify bookmarlet中：

function getScript(url, success) {
    var script = document.createElement('script');
    script.src = url;
    var head = document.getElementsByTagName('head')[0],
        done = false;
    // Attach handlers for all browsers
    script.onload = script.onreadystatechange = function() {
      if (!done && (!this.readyState
           || this.readyState == 'loaded'
           || this.readyState == 'complete')) {
        done = true;
        success();
        script.onload = script.onreadystatechange = null;
        head.removeChild(script);
      }
    };
    head.appendChild(script);
}
getScript('http://code.jquery.com/jquery-latest.min.js',function() {
    // Yay jQuery is ready \o/
});​