Pass an array from jQuery POST to C# WebApi

Question

I am trying to pass an array from a jQuery POST to a C# WebApi service, but I get the following error:

object reference not set to an instance of an object.

jQuery code:

 $(document).ready(function ()
    {
        $("#btn").click(function ()
        {
          var purchases = { dealid1: ["2", "3", "4"], theatid1: "5", mouvid1: "408", bookdt1: "10/11/2015", shtime1: "11:00AM", fbid1: "100" };
           $.ajax(
            {
                type: "POST",
                data: { purchases },
                url: "api/purchase",
                contentType: "application/json"
            });
        });
    });
<input type="button" value="mybtn" id="btn" />

WebApi code:

 public object post([FromBody] purchase purchases)
    {
        return Request.CreateResponse(jsonvalues(purchases));
    }

    private object jsonvalues(purchase purchases)
    {
        object result = false;
        for (int i = 0; i < purchases.dealid1.Length; i++)//I got error here//
        {
           int count= purchases.dealid1.Count();
            dealid = purchases.dealid1;
            string arr = dealid[i];
        }
            theatid = purchases.theatid1;
            mouvid = purchases.mouvid1;
            bookdt = purchases.bookdt1;
            shtime = purchases.shtime1;
            fbid = purchases.fbid1;
    }
 public class purchase
{
    public string[] dealid1 { get; set; }
    public string theatid1 { get; set; }
    public string mouvid1 { get; set; }
    public string bookdt1 { get; set; }
    public string shtime1 { get; set; }
    public string fbid1 { get; set; }

}

I am able to get other values like theatid1, mouvid1, etc. But dealid1 is not accessible. Any ideas what I'm doing wrong?

Possible duplicate of [What is a NullReferenceException and how do I fix it?](http://stackoverflow.com/questions/4660142/what-is-a-nullreferenceexception-and-how-do-i-fix-it) — Steve, Nov 05 '15 at 05:12
Try changing `data: { purchases }` to `data: purchases`. You wrap an object into an object. Why? — Yeldar Kurmangaliyev, Nov 05 '15 at 05:13
@KaushikMaheta; "object reference not set to an instance of an object". — Unnikrishnan.S, Nov 05 '15 at 05:17
@YeldarKurmangaliyev:still i got the same error "object reference not set to an instance of an object" — Unnikrishnan.S, Nov 05 '15 at 05:22
data: JSON.stringify( purchases ); replace this line and try it. — Kaushik Maheta, Nov 05 '15 at 05:23

score 0 · Accepted Answer · edited Nov 06 '15 at 05:44

$(document).ready(function ()
{
    $("#btn").click(function ()
    {
      var purchases = { dealid1: ["2", "3", "4"], theatid1: "5", mouvid1: "408", bookdt1: "10/11/2015", shtime1: "11:00AM", fbid1: "100" };
       $.ajax(
        {
            type: "POST",
            data: JSON.stringify( purchases ),
            url: "api/purchase",
            contentType: "application/json"
        });
    });
});

Pass an array from jQuery POST to C# WebApi

1 Answers1