how to get the individual parameters from the list of dynamic parameters in a webmethod,sent using jquery ajax method?

Question

hi, I am using jquery ajax method on my aspx page,which will invoke the webmethod in the code behind.Currently the webmethod takes a couple of parameters like firstname,lastname,address etc which I am passing from jquery ajax method using

data:JSON.stringify({fname:firstname,lname:lastname,city:city})

now my requirement has been changed such that,the number and type of parameters that are going to be passed is not fixed for ex.parameter combination can be something like fname,city or fname,city or city,lname or fname,lname,city or something else.So the webmethod should be such that it should accept any number parameters.I thought of using arrays to do so, as described here.

But I do not understand how can I identify which and how many parameters have been passed to the webmethod to insert/update the data to the DB.Please could someone help me with this?

thanks

Answer 1

You could return a single JSON string parameter and parse it on the server within your webmethod.

This is just one approach. Another might be to take a look at your overall design and think about how you might improve it so that you don't have to pass variable parameters around. they can be nasty, as you have found. Often, stepping back and refactoring can lead to a simpler, more elegant design that is a lot easier to program.

Answer 2

You would just add the parameters to your object, depending on their availability/presence:

var params = {};
if(city != null) {
    params.city = city;
}
params.fname = $("#fname").val();
...etc...

$.ajax({
    ...
    data:JSON.stringify(params);
    ...
});

Answer 3

I would pass the webmethod a string in specific format (maybe the format of your first example)

That way when you get the requeston the server you first split it on "," to get an array of name value pairs and then split each pair to get the individual name and value parts.

Keeps the call simple and you can handle it with complex code on the server with the fluffy .Net frameworks intellisense to help you out.

KISS = Keep It Simple Stupid

My old music teacher used to live by that, I only realised why recently !!!!

Answer 4

You can use a complex type on the client side that matches an object on the server side that contains an array or several arrays of your parameters.

Very crude example

(server side)

//class declaration     
public class MyObject
{
      //values
      string[] Keys;
      string[] Values;

      //methods
      public void Add()
      {...} 
}

//web service - WebService.asmx
[WebMethod]
public void AddObject(MyObject NewObject)
{
     NewObject.Keys.Length = ...;
     NewObject.Add();
     ...
}

(client side)

var MyObject= { };

MyObject.Keys = { $("#key1").val(), $("#key2").val(), ... };
MyObject.Values = { $("#val1").val(), $("#val2").val(), ... };

var DTO = { 'MyObject' : MyObject};

$.ajax({
   type: "POST",
   contentType: "application/json; charset=utf-8",
   url: "WebService.asmx/AddObject",
   data: JSON.stringify(DTO),
   dataType: "json"
});

The above example will serialize your object on the client side and you will be able to access the object on the server side just as if you created it with new().