webservice error 500 Internal Error asp.net

Question

I have written a webservice call in JQuery in document ready function but its not calling the function

Below is the code JQuery

`<script type="text/javascript">
$( document ).ready(function() {
var section = "Table - TLI (STOCK)";
$.ajax({
type: "GET",contentType: "application/json; charset=utf-8",
        url: "pgWebService.aspx/SliderBlock",
        dataType: "json",
        data: "{'section':'" + section + "'}",
        success: function (res) {
            //$("#Text1").val(res.text);
            console.log(res);
            alert("DONE");
        }
    });
});
</script>`

C# Code pgWebService

public static string SliderBlock(string section)
{
    string html = "<ul class='maketabs listing-table search-filter change-view'>";
    SqlConnection cn = new SqlConnection(ConfigurationManager.ConnectionStrings["TLI"].ConnectionString);
    SqlCommand cmd = new SqlCommand();
    cn.Open();
    cmd.Connection = cn;
    cmd.CommandText = "Select * from CategoryDetails where section=" + section;
    SqlDataReader rs = cmd.ExecuteReader();
    while (rs.Read())
    {
        html="<li>"+rs.getValue(0).toString()+"</li>";
    }
    rs.Close();
    cmd.Dispose();
    cn.Close();
    html = html + "</ul>";
    return html;
}

Is it in code behind or in separate webserivce ? – Mairaj Ahmad May 04 '15 at 09:13 — Mairaj Ahmad, May 04 '15 at 09:13

Mairaj Ahmad · Accepted Answer · 2015-05-04T09:50:16.117

2

If your method SliderBlock is in code behind than make your method WebMethod to be called by ajax.Also you need to make it static and to be called by GET you need to enable GET requests on your WebMethod.

[System.Web.Services.WebMethod]
[System.Web.Script.Services.ScriptMethod(UseHttpGet = true)]
public static string SliderBlock(string section)
{
//Your code here
}

edited May 04 '15 at 09:50

answered May 04 '15 at 09:21

Mairaj Ahmad

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@naveen thnks.Updated it, – Mairaj Ahmad May 04 '15 at 09:50
@MairajAhmad got the point and i made the necessary changes but still its giving me 500 Internal Error – bhavikshah28 May 04 '15 at 10:37
Can u check in browser console to see the detailed error and post it here. – Mairaj Ahmad May 04 '15 at 10:38
i have a different page in which i am calling the webservice and the pgWebservice.aspx page is different the error in console is as below:GET http://localhost:1312/PMS/pgWebService.aspx/SliderBlock [HTTP/1.1 500 Internal Server Error 27ms] – bhavikshah28 May 04 '15 at 10:41
Yes click the link in console to see details. – Mairaj Ahmad May 04 '15 at 10:45

score 0 · Answer 2 · answered May 04 '15 at 09:48

As your code has the extension .aspx I assume that you are using the code-behind ( Page Method ). So you need to make these changes to your function signature

[System.Web.Services.WebMethod]
public static string SliderBlock(string section)

That is,

your method should be static.
your method should be decorated with System.Web.Services.WebMethod

And in your $.ajax call, change the dataType to json.

dataType: "json"

Also, please bear in mind that the PageMethid in pgWebService.aspx.cs can be only called from pgWebService.aspx

how can i call a text changed event of the textbox from a webmethod?? — bhavikshah28, May 08 '15 at 09:56

score 0 · Answer 3 · answered May 04 '15 at 10:54

You still have errors in the ajax request:

Content-Type: When sending data to the server, use this content type. But you are not sending data to the server except the query string parameters because you are doing a GET. So, if you inspect with webbrowser developer tools the request you see a GET with this URL: localhost/pgWebService.aspx/SliderBlock?section=selectedSection because...

Data: Data to be sent to the server. It is converted to a query string, if not already a string. It's appended to the url for GET-requests.

dataType: The type of data that you're expecting back from the server. But in your webService your are returning a string with HTML not JSON.

can u give some example on it – bhavikshah28 May 04 '15 at 11:57 — bhavikshah28, May 04 '15 at 11:57

webservice error 500 Internal Error asp.net

3 Answers3

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