extjs源码分析-009(Ext.urlDecode/urlEncode)

//把json格式转化成url的编码方式
// e.g. Ext.urlEncode({foo: 1, bar: 2}); would return "foo=1&bar=2"
urlEncode: function(o, pre){//o为json对象,pre为前缀
            var undef, buf = [], key, e = encodeURIComponent;

            for(key in o){
                undef = !Ext.isDefined(o[key]);
                Ext.each(undef ? key : o[key], function(val, i){
                    buf.push("&", e(key), "=", (val != key || !undef) ? e(val) : "");
                });
            }
            if(!pre){
                buf.shift();
                pre = "";
            }
            return pre + buf.join('');
        },
//把URL字符串编码转化成json对象
//Ext.urlDecode("foo=1&bar=2"); // returns {foo: "1", bar: "2"}
//Ext.urlDecode("foo=1&bar=2&bar=3&bar=4", false); // returns {foo: "1", bar: ["2", "3", "4"]}

urlDecode : function(string, overwrite){//string URL参数,overwrite针对同一参数的多个值是否覆盖,false为不覆盖,那就返回这个参数的数组
            var obj = {},
                pairs = string.split('&'),
                d = decodeURIComponent,
                name,
                value;
            Ext.each(pairs, function(pair) {
                pair = pair.split('=');
                name = d(pair[0]);
                value = d(pair[1]);
                obj[name] = overwrite || !obj[name] ? value :
                            [].concat(obj[name]).concat(value);
            });
            return obj;
        }