获取url参数内容

function getUrlPar(name) {
    var reg = new RegExp("(^|&)" + name + "=([^&]*)(&|$)", "i");
    var url = decodeURI(decodeURI(window.location.search))
    var r = url.substr(1).match(reg);
    if (r != null) return unescape(r[2]);
    return null;
}