Auto Save Using AJAX

Introduction

 

This article explains how to automatically save a value into a SQL database using an ASP.Net WebMethod and jQuery Ajax.

 

jQuery

 

The following code shows that SaveDraft.aspx is the aspx page and AutoSave is the method. We pass the client-side value to the server-side using Ajax and WebMethod.

$(document).ready(function () {
      // Configure to save every 5 seconds
      window.setInterval(saveDraft, 5000);//calling saveDraft function for every 5 seconds

});

// ajax method
function saveDraft() {

   $.ajax({
       type: "POST",
       contentType: "application/json; charset=utf-8",
       url: "SaveDraft.aspx/AutoSave",
       data: "{'firstname':'" + document.getElementById('Firstname').value + "','middlename':'" + document.getElementById('Middlename').value + "','lastname':'" + document.getElementById('Lastname').value + "'}",

      success: function (response) {

      }

  });
}

In the following code the saveDraft function fires every 5 seconds. The value will be saved in the database every 5 seconds without post-backs. Based on our requirements we can change the time interval. 

$(document).ready(function () {
     // Configure to save every 5 seconds
     window.setInterval(saveDraft, 5000);//calling saveDraft function for every 5 seconds

});

Database structure

 

Create a table in a database for storing the personal information.The following SQL code contains an existing person's details. So we can change those values at runtime without a post-back and button-click. 

USE [TestDB]
GO
/****** Object:  Table [dbo].[Autosave]    Script Date: 08/07/2015 18:19:54 ******/
SET ANSI_NULLS ON
GO
SET QUOTED_IDENTIFIER ON
GO
CREATE TABLE [dbo].[Autosave](
    [Id] [int] NULL,
    [firstname] [nvarchar](50) NULL,
    [middlename] [nvarchar](50) NULL,
    [lastname] [nvarchar](50) NULL
) ON [PRIMARY]
GO
INSERT [dbo].[Autosave] ([Id], [firstname], [middlename], [lastname]) VALUES (1, N'Rajeesh', N'', N'Menoth')

C#

 

The WebMethod will catch the client-side value in the server side. In the given example I am passing the id directly into the update query. You can modify the code for your requirements. 

[WebMethod]
    public static string AutoSave(string firstname, string middlename, string lastname)
    {
        int id = 1;
        string ConnectionString = System.Configuration.ConfigurationManager.ConnectionStrings["TestDb"].ConnectionString;
        SqlConnection con = new SqlConnection(ConnectionString);
        {
            string str = "Update Autosave set firstname='" + firstname + "',middlename= '" + middlename + "',lastname= '" + lastname + "' where Id=" + id + "";
            SqlCommand cmd = new SqlCommand(str, con);
            {
                con.Open();
                cmd.ExecuteNonQuery();
                return "True";
            }
        }

    }

Important Section

 

1. Namespace 

 

The given namespace contains the WebMethod,database connection libraries.

using System.Web.Services;
using System.Data.SqlClient;

2. Reference

 

Add the following jQuery reference.

<script type="text/javascript" src="http://ajax.googleapis.com/ajax/libs/jquery/1.4.2/jquery.min.js"></script>
script type="text/javascript" src="http://ajax.googleapis.com/ajax/libs/jqueryui/1.8.1/jquery-ui.min.js"></script>

 
                                                            Figure 1

Output

 

 
                                                            Figure 2

 

Reference

•  Tech Blog Content

Summary 

We learned how to automatically save a value into a SQL database using ASP.Net WebMethod and jQuery Ajax. I hope this article is useful for all .NET beginners.