Parse GET query string in JavaScript

parseQuery.js

function parseQuery(str){
	var ret = {};
	str.split("&").forEach(function(value){
		var data = value.split('='),
			name = decodeURIComponent(data.shift()),
			val = decodeURIComponent(data.join("=")).replace('+', ' '),
			nameVal = name.match(/(.*)\[(.*)\]/);

		if(nameVal === null){
			ret[name] = val;
		}
		else{
			name = nameVal[1];
			nameVal = nameVal[2];
			if(nameVal === ''){
				if(ret[name] && Array.isArray(ret[name])){
					ret[name].push(val);
				}
				else{
					ret[name] = [val];
				}
			}
			else{
				if(!ret[name]){
					ret[name] = {};
				}
				ret[name][nameVal] = val;
			}
		}
	});
	return ret;
}

Updated to support param2[key1]=value1&param2[key2]=value2 :-)

Removed jQuery dependency.