In this article I will explain with an example, how to return HttpResponse from Web Service (ASMX) in ASP.Net using C# and VB.Net.
The Web Service (ASMX) will return the HttpResponse along with HttpStatusCode in ASP.Net.
 
 

Namespaces

You will need to import the following namespace.
C#
using System;
using System.Web;
using System.Web.Services;
using System.IO;
using System.Net;
 
VB.Net
Imports System.Web
Imports System.Web.Services
Imports System.Web.Services.Protocols
Imports System.IO
Imports System.Net
 
 

Web Service (ASMX) for returning the HttpResponse.

This Web Service (ASMX) returns an OK response along with HttpStatusCode to the Client.
C#
/// <summary>
/// Summary description for Service
/// </summary>
[WebService(Namespace = "http://tempuri.org/")]
[WebServiceBinding(ConformsTo = WsiProfiles.BasicProfile1_1)]
// To allow this Web Service to be called from script, using ASP.NET AJAX, uncomment the following line.
//[System.Web.Script.Services.ScriptService]
public class Service : System.Web.Services.WebService
{
 
    public Service()
    {
        //Uncomment the following line if using designed components
        //InitializeComponent();
    }
 
    [WebMethod]
    public void CheckStatus()
    {
        //Send OK Response to Client.
        HttpContext.Current.Response.StatusCode = (int)HttpStatusCode.OK;
        HttpContext.Current.Response.Write("OK");
    }
}
 
VB.Net
' To allow this Web Service to be called from script, using ASP.NET AJAX, uncomment the following line.
'<System.Web.Script.Services.ScriptService()> _
<WebService(Namespace:= "http://tempuri.org/")> _
<WebServiceBinding(ConformsTo:= WsiProfiles.BasicProfile1_1)>
<Global.Microsoft.VisualBasic.CompilerServices.DesignerGenerated()>
Public Class Service
    Inherits System.Web.Services.WebService
 
    <WebMethod()>
    Public Sub CheckStatus()
        'Send OK Response to Client.
        HttpContext.Current.Response.StatusCode = CInt(HttpStatusCode.OK)
        HttpContext.Current.Response.Write("OK")
    End Sub
End Class
 
 

Adding Web Reference of Web Service

Next thing you need to do is add the Web Reference of the Web Service so that it can be used on the ASP.Net Web page.
Please refer the following article for instructions in adding Web Reference of Web Service: How to add reference of Web Service (ASMX) in ASP.Net using Visual Studio.
 
 

HTML Markup

The HTML Markup consists of an HTML Button.
The Button has been assigned a jQuery Click event handler. When the Button is clicked, the Web Service (ASMX) is called using jQuery AJAX.
The HttpResponse along with HttpStatusCode are received in the Success event handler which are later displayed using JavaScript Alert Message Box.
<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
    <title></title>
</head>
<body>
    <form id="form1" runat="server">
        <input type="button" id="btnCheck" value="Check Status" />
        <script type="text/javascript" src="https://ajax.googleapis.com/ajax/libs/jquery/3.7.1/jquery.min.js"></script>
        <script type="text/javascript">
            $("body").on("click", "#btnCheck", function () {
                $.ajax({
                     url: 'Service.asmx/CheckStatus',
                     type: 'POST',
                     data: {},
                     success:function (data,textStatus, http) {
                        alert("Data: " + data + "\nTextStatus: " + textStatus + "\nHttpStatus: " + http.status);
                    },
                     error: function (r) {
                        alert(r.responseText);
                    },
                     failure: function (r) {
                        alert(r.responseText);
                    }
                });
            });
        </script>
    </form>
</body>
</html>
 
 

Screenshot

Returning HttpResponse from Web Service (ASMX) in ASP.Net
 
 

Downloads

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