一些js

var obj = {};
    obj.SystemCode = code;
    obj.pageIndex = pageIndex;

$.post(url, obj,function (result) {
                );
        });

{“SystemCode”:"code","pageIndex":“pageIndex”}

{“SystemCode”:null}的形式

//将字符串"null"或null转换为""
function checkNull(temp) {
    if (temp == null)
        temp= "";
    if (temp.toString().toLowerCase() == "null")
        temp = "";
    return temp;
}