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;
}