Js插件—替换地址栏参数

/*

js替换URL参数值，无该参数则添加

例：http://www.daoyan.com/aaa.htm?cid=aaa&cname=zhangsan

使用：subUrlParam(‘cid‘,"bbb");将返回 http://www.daoyan.com/aaa.htm?cid=bbb&cname=zhangsan

*/

/*

替换地址栏参数值

paramName为参数名

paramValue为参数值

如果有多个参数，则把剩余参数组装成name=value&name1=value1....格式的字符串传入

例如：subUrlParam("cid","bbb","name=zhangsan&age=18")

*/

function subUrlParam(paramName, paramValue) {

    var
result; //返回的新地址

    var
args; //多个参数

    if
(arguments.length > 2) args = arguments[2];

    var
s = window.location.search; //获取传递的参数。如：?cid=bbb&cname=zhangsan

    if
(s != null
&& s.length > 1) {

        var
u = s.substr(1); //去掉参数前面的问号

        var
parr = u.split("&");

        //如果地址栏不包含传递的参数，则直接添加该参数

        if
(u.indexOf(paramName) < 0) {

            u += "&"
+ paramName + "="
+ paramValue;

        } else
{

            for
(var
i = 0; i < parr.length; i++) {

                var
arr = parr[i].split("="); //分割地址栏参数，cid=aaa

                //如果当前的参数名和传递的参数名相同，则把当前参数的值替换成传递的值

                if
(arr[0] == paramName) {

                    u = u.replace(parr[i], paramName + "="
+ paramValue);

                    break;

                }

            }

        }

        //遍历传递进来的多个参数集合，并和原来地址栏上的参数集合对比，如果存在该参数则替换其值，不存在则直接添加该参数

        if
(args != null
&& args.length > 0) {

            var
aparr = args.split("&");

            for
(var
i = 0; i < aparr.length; i++) {

                var
ishas = false; //是否存在该参数

                var
ap = aparr[i].split("=");

                for
(var
n = 0; n < parr.length; n++) {

                    var
arr = parr[n].split("=");

                    if
(arr[0] == ap[0]) {

                        ishas = true;

                        u = u.replace(parr[n], aparr[i]);

                        break;

                    }

                }

                //原来参数集合中不存在该参数则添加

                if
(!ishas) {

                    u += "&"
+ aparr[i];

                }

            }

        }

        result = location.pathname + "?"
+ u;

    } else
{

        //地址栏没有参数时，直接添加传递的参数

        result = location.href + "?"
+ paramName + "="
+ paramValue;

        if
(args != null
&& args.length > 0) {

            result += args;

        }

    }

    return
result;

}