javascript获取url参数

<script type="text/javascript">
//获取QueryString的数组
function getQueryString() {
    var result = location.search.match(new RegExp("[\?\&][^\?\&]+=[^\?\&]+", "g"));
    if (result == null) {
        return "";
    }
    for (var i = 0; i < result.length; i++) {
        result[i] = result[i].substring(1);
    }
    return result;
}
//根据QueryString参数名称获取值
function getQueryStringByName(name) {
    var result = location.search.match(new RegExp("[\?\&]" + name + "=([^\&]+)", "i"));
    if (result == null || result.length < 1) {
        return "";
    }
    return result[1];
}
//根据QueryString参数索引获取值
function getQueryStringByIndex(index) {
    if (index == null) {
        return "";
    }
    var queryStringList = getQueryString();
    if (index >= queryStringList.length) {
        return "";
    }
    var result = queryStringList[index];
    var startIndex = result.indexOf("=") + 1;
    result = result.substring(startIndex);
    return result;
}
alert(getQueryString())
alert(getQueryStringByName("user"))
alert(getQueryStringByIndex("0"))
alert(getQueryStringByIndex("1"))
</script>