title: How to use Ajax with Multi Array Objects by JSON from client to server side (C#)
body: <p>How can I do with following questions?<br>
  1. Front-end site question is how to transfer Object-Array to JSON?<br>
  2. Back-end site question is how to get the JSON data from front-side?    </p>
  
  <h2>Question 1:</h2>
  
  <blockquote>
    <p>how to make a data parameter in the AJAX?</p>
  </blockquote>
  
  <pre><code> var vItems = [];
          var vItem = new Item('1', '11');
          vItems.push(vItem);
          vItem = new Item('2', '22');
          vItems.push(vItem);    
  
   function Item(Key,Val) {
          this.Key = Key;
          this.Val = Val;
      }
  
   $.ajax({
              type: "POST",
              url: ".............",
              data: ????????????????????  ,
              contentType: "application/json; charset=utf-8",
              dataType: "json",
              success: function (response) {
                  alert(response.d);  
              },
              failure: function (response) {
                  alert(response.d);
              }
          });
  </code></pre>
  
  <h2>Question 2:</h2>
  
  <blockquote>
    <p>How to make a correct parameter with C# function</p>
  </blockquote>
  
  <pre><code> [System.Web.Services.WebMethod]
   public static string xxx(?????????)
   {    
          return "";
   }     
   public class VItems
   {
          public string Key;
          public string Val;
   }
  </code></pre>
  
  <p>PS: Please I've to use the same class between front-side and back-side like    </p>
  
  <p>Front-Side   </p>
  
  <pre><code>         function Item(Key,Val) {
                       this.Key = Key;
                       this.Val = Val;
                   }
  </code></pre>
  
  <p>Back-Side    </p>
  
  <pre><code>         public class VItems {
                       public string Key;
                       public string Val;
                   }
  </code></pre>
  
  <p>By the way, this issue isn't duplicative 
  <a href="https://stackoverflow.com/questions/18078957/pass-a-user-defined-object-to-asp-net-webmethod-from-jquery-using-json">URL</a>
  because it is just only one array-object, I need to handle multiple
  data</p>