Pass (Send) string value from Generic Handler (ashx) to aspx page using C# and VB.Net

Hi suhaas121,

Check this example. Now please take its reference and correct your code.

Namespaces

C#

using System.Net;
using System.Web.Script.Serialization;

VB.Net

Imports System.Net
Imports System.Web.Script.Serialization

Code

C#

protected void Button1_Click(object sender, EventArgs e)
{
    Product product = new Product();
    product.status = "SUCCESSFUL";
    JavaScriptSerializer js = new JavaScriptSerializer();
    // Get the Json response from the api.
    string response = js.Serialize(product);
    string responseData = (new WebClient()).DownloadString("http://localhost:54496/Handler.ashx?Json=" + response);
    if (responseData != "")
    {
        ClientScript.RegisterStartupScript(this.GetType(), "message", "alert('" + responseData + "');", true);
    }
}

public class Product
{
    public string status { get; set; }
}

VB.Net

Protected Sub Button1_Click(ByVal sender As Object, ByVal e As EventArgs)
    Dim product As Product = New Product()
    product.status = "SUCCESSFUL"
    Dim js As JavaScriptSerializer = New JavaScriptSerializer()
    Dim response As String = js.Serialize(product)
    Dim responseData As String = (New WebClient()).DownloadString("http://localhost:54496/Handler.ashx?Json=" & response)
    If responseData <> "" Then
        ClientScript.RegisterStartupScript(Me.GetType(), "message", "alert('" & responseData & "');", True)
    End If
End Sub

Public Class Product
    Public Property status As String
End Class

Generic Handler

C#

<%@ WebHandler Language="C#" Class="Handler" %>

using System;
using System.Web;
using System.Web.SessionState;
using System.Web.Script.Serialization;

public class Handler : IHttpHandler, IRequiresSessionState
{
    public void ProcessRequest(HttpContext context)
    {
        if (context.Request.QueryString["Json"] != null)
        {
            string json = context.Request.QueryString["Json"];
            JavaScriptSerializer js = new JavaScriptSerializer();
            Product product = js.Deserialize<Product>(json);
            string y = product.status;
            string output = "";
            if (y == "PENDING")
            {
                output = "THANK YOU";
            }
            context.Response.ContentType = "text/plain";
            context.Response.Write(output);
        }
    }

    public bool IsReusable
    {
        get
        {
            return false;
        }
    }

    public class Product
    {
        public string status { get; set; }
    }
}

VB.Net

<%@ WebHandler Language="VB" Class="Handler" %>

Imports System
Imports System.Web
Imports System.Web.Script.Serialization

Public Class Handler : Implements IHttpHandler
    Public Sub ProcessRequest(ByVal context As HttpContext) Implements IHttpHandler.ProcessRequest
        If context.Request.QueryString("Json") IsNot Nothing Then
            Dim json As String = context.Request.QueryString("Json")
            Dim js As JavaScriptSerializer = New JavaScriptSerializer()
            Dim product As Product = js.Deserialize(Of Product)(json)
            Dim y As String = product.status
            Dim output As String = ""
            If y = "PENDING" Then
                output = "THANK YOU"
            End If
            context.Response.ContentType = "text/plain"
            context.Response.Write(output)
        End If
    End Sub

    Public ReadOnly Property IsReusable() As Boolean Implements IHttpHandler.IsReusable
        Get
            Return False
        End Get
    End Property

    Public Class Product
        Public Property status As String
    End Class
End Class