Archive for May, 2016

Auto Save Using Ajax

Posted: May 7, 2016 in Ajax, ASP.Net, Jquery
0

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: 07/05/2016 11:19:54 ******/
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'Sachin', N'', N'Mortale')

 

C# Code

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.

http://ajax.googleapis.com/ajax/libs/jquery/1.4.2/jquery.min.js
http://ajax.googleapis.com/ajax/libs/jqueryui/1.8.1/jquery-ui.min.js



Figure 1

Figure 1

Figure 2

Figure 2

Summary

We learned how to automatically save a value into a SQL database using ASP.Net WebMethod and jQuery Ajax.