javascript获取页面url的参数

/**
 * 获取URL上的参数
 * @param {Object} name
 */
function getURLParam(name) {
 var reg = new RegExp("(^|&)" + name + "=([^&]*)(&|$)", "i");
 var r = window.location.search.substr(1).match(reg);
 var context = "";
 if(r != null) {
  context = r[2];
 }
 reg = null;
 r = null;
 return context == null || context == "" || context == "undefined" ? "" : context;
}