How to call c# method with no parameters and access returned data?

c# javascript jquery ajax json

12,631

If your method takes no arguments, just don't specify the data property on the ajax call

<script>
  $(function () {
    $.ajax({
      url: 'WebService.asmx/getList',
      type: 'POST',
      dataType: 'json', //make sure your service is actually returning json here
      contentType: 'application/json',
      success: function (data, status) {
        //here data is whatever your WebService.asmx/getList returned
        //populate your dropdown here with your $.each w/e
      }
    });
  });
</script>

Also I could be wrong, but the WebService method you showed, doesn't look like it will return json. I think you will have to serialize, or set the content type or something similar. (Been along time since I've used the asmx type services)

12,631

Author by

loonyuni

Updated on June 14, 2022

Comments

loonyuni almost 2 years

So I have seen many examples such as these : https://stackoverflow.com/a/8094230/2525507

public class WebService : System.Web.Services.WebService {
   [WebMethod]
   public List<string> getList() {
      return new List<string> {"I", "Like", "Stack", "Overflow"};
   }
}

Where you just it seems that through the success function you can view the returned data from the c# method in the form of an alert. But what if I want to access this "input+1" data outside of the function call, how would I proceed to do that? Also I am not sure how to call a method that has no parameters?

<body>

<select id="wordSelect">
// Drop Down Menu to be populated 
</select>

<script>
  $(function () {
    $.ajax({
      url: 'WebService.asmx/getList',
      data: '{**NO PARAMETERS?!**}', // should I also call JSON.stringify?
      type: 'POST',
      dataType: 'json',
      contentType: 'application/json',
      success: function (data, status) {
        alert(data);
        alert(typeof data);
      }
    });
  });

 $.each(data.i, function(index, item) { // will this access "I", "Like", ... etc?
     $(#wordSelect).append(
         $("<option></option>")
             .text(item)
     );
 };
</script>

</body>

In the end, I would like to populate a dropdown list using returned JSON data from a c# method that has been called through ajax, but I'm not sure how I can play with that retrieved JSON data that seems to be stuck in the function call?

Sorry, I am new to Jquery/AJAX/etc... But Thank you so much!

loonyuni almost 10 years

Thank you guys! Sorry this was such a trivial question, but I really couldn't Google with the correct terminology or find apt examples. Thank you thank you thank you!
loonyuni almost 10 years

So I have tried to just access data in my success call, but I keep getting an error saying "data" is undefined? Any ideas?
Kyle Gobel almost 10 years

is data the first parameter of your success callback?
loonyuni almost 10 years

It's all good turns out my my webservice was nested and I messed up the url.