(function() {
	var cross = {
		//设置一个随机的callback函数..防止跟其他的全局函数重名
		callback : 'cross' + parseInt(Math.random()*1000),
		init : function() {
			this.getJSON('http://to.ly/api.php?json=1&longurl='+encodeURIComponent('http://www.skiyo.cn/'), function(data){
				alert(data.shorturl);
			});
		},
		getJSON : function(url, callback) {
			var c = this.callback;
			url = url + "&callback=" + c;
			// Handle JSONP-style loading
			//将函数名设置为window的一个方法,这样此方法就是全局的了.
			window[ c ] = window[ c ] || function( data ) {
				//调用匿名函数
				callback(data);
				// Garbage collect
				window[ c ] = undefined;
				try {
					delete window[ c ];
				} catch(e) {}
				if ( head ) {
					head.removeChild( script );
				}
			};
			var head = document.getElementsByTagName("head")[0] || document.documentElement;
			var script = document.createElement("script");
			script.src = url;
			// Handle Script loading
			var done = false;
			// Attach handlers for all browsers
			script.onload = script.onreadystatechange = function() {
				if ( !done && (!this.readyState 
						this.readyState === "loaded" || this.readyState === "complete") ) {
					done = true;
					// Handle memory leak in IE
					script.onload = script.onreadystatechange = null;
					if ( head && script.parentNode ) {
						head.removeChild( script );
					}
				}
			};
			head.insertBefore( script, head.firstChild );
		},
	};
	//go
	cross.init();
})();