通过ajax调用传递的javascript对象（使用JSON序列化的客户端）的服务器端类型是什么？

Question

This is not the clearest of question titles, sorry about that, but I will try and break down my issue as best I can.

I have some client side javascript, and am trying to make an ajax server side call, passing through some data. I am serialising this data using JSON.

$.ajax({
    type: "POST",
    contentType: "application/json; charset=utf-8",
    data: stringifyData(dataToStringify)
    dataType: "json",
});

stringifyData = function (dataToStringify){
    var requestParameters = {};
    requestParameters.requestData = dataToStringify;
    return JSON.stringify(requestParameters)
}

This is the code I am using, which works fine.

//client side JS
var dataToStringify = 'John'
//Becomes- '{"requestData":"John Smith"}'

//server side c#
[WebInvoke(Method = "POST")]
public string ajaxCall(string requestData){
    //stuff
}

If I serialise a simple string, it deserialises to a string.

//client side JS
var dataToStringify = {}
dataToStringify.FirstName = 'John'
dataToStringify.SurName = 'Smith'
//Becomes- '{"requestData":{"Firstname":"John","Surname":"Smith"}}'

//server side c#
public class Person {
    string Firstname {get;set;}
    string Surname {get;set;}
}

[WebInvoke(Method = "POST")]
public string ajaxCall(Person requestData){
    //stuff
}

If I serialise a javascript object, then it deserialises to an appropriate server side object (has all keys defined).

//client side JS
var dataToStringify = {}
dataToStringify.Key1 = 'Val1'
dataToStringify.Key2 = 'Val2'
...
dataToStringify.Keyn = 'Valn'
//Becomes- '{"requestData":{"Key1":"Val1","Key2":"Val2"...,,"Keyn":"Valn"}}'

//server side c#
[WebInvoke(Method = "POST")]
public string ajaxCall(??? requestData){
    //stuff
}   

My problem is that I am trying to pass an object where the keys are not all known - a simple list of key/value pairs. But I cannot get it to deserialise correctly. Using 'Dictonary' as the server side type does not work, nor does a generic 'Object'.

In my last example, what type should the reqestData object be? Is what I am trying to achieve possible?

Many thanks.

Answer 1

@Etch's answer is on the right track, but if I remember correctly, KeyValuePair isn't very serialization-friendly.
you can define a simple (key, value) struct of your own, and pass that:

struct JSONableKeyValuePair
{
   public string Key;
   public string /*or whatever type*/ Value;
}

and then your json should be an array of those, looking something like:
[ {'Key' : 'key 1', 'Value': 'value 1'}, {'Key' : 'key 2', 'Value': 'value 2'}]

Answer 2

If you change your json for calling the service to

"requestData":[{"Key1":"Val1"},{"Key2":"Val2"}]

That should work with KeyValuePair<string,string> . I havent tried to use KeyValuePair but I use List<> in this fashion.

Edit

After looking over my services I noticed I do not use List<> however I use an array. so in your case:

public string ajaxCall(Person[] requestData){
}