Introduction
Today, in this article let's play around with one of the interesting and most useful concepts in LINQ to XML.
Question: What is update data to XML using LINQ to XML?
In simple terms "It provides flexibility to update data in XML with the help of a LINQ query."
Step 1: Create a new "ASP.NET Web Application", as in:
![Output1.jpg]()
Step 2: The complete code of Employee.xml looks like this:
<?xml version="1.0" encoding="utf-8"?>
<Employees>
<Employee>
<Id>1</Id>
<FirstName>Vijay</FirstName>
<LastName>Prativadi</LastName>
<Age>26</Age>
</Employee>
<Employee>
<Id>2</Id>
<FirstName>Sandeep</FirstName>
<LastName>Reddy</LastName>
<Age>28</Age>
</Employee>
</Employees>
Step 3: The complete code of webform1.aspx looks like this:
<%@ Page Language="C#" AutoEventWireup="true" CodeBehind="WebForm1.aspx.cs" Inherits="LINQtoXMLUpdateApp.WebForm1" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head id="Head1" runat="server">
<title></title>
</head>
<body>
<form id="form1" runat="server">
<center>
<div>
<table>
<tr>
<td colspan="2" align="center">
<asp:Label ID="Label1" runat="server" Text="Update Data using LINQ-to-XML" Font-Bold="true"
Font-Size="Large" Font-Names="Verdana" ForeColor="Maroon"></asp:Label>
</td>
</tr>
<tr>
<td>
<asp:Label ID="Label6" runat="server" Text="Please Enter Id" Font-Size="Large" Font-Names="Verdana"
Font-Italic="true"></asp:Label>
</td>
<td>
<asp:TextBox ID="TextBox4" runat="server"></asp:TextBox>
</td>
</tr>
<tr>
<td>
<asp:Label ID="Label2" runat="server" Text="Please Enter FirstName" Font-Size="Large"
Font-Names="Verdana" Font-Italic="true"></asp:Label>
</td>
<td>
<asp:TextBox ID="TextBox1" runat="server"></asp:TextBox>
</td>
</tr>
<tr>
<td>
<asp:Label ID="Label3" runat="server" Text="Please Enter LastName" Font-Size="Large"
Font-Names="Verdana" Font-Italic="true"></asp:Label>
</td>
<td>
<asp:TextBox ID="TextBox2" runat="server"></asp:TextBox>
</td>
</tr>
<tr>
<td>
<asp:Label ID="Label4" runat="server" Text="Please Enter Age" Font-Size="Large" Font-Names="Verdana"
Font-Italic="true"></asp:Label>
</td>
<td>
<asp:TextBox ID="TextBox3" runat="server"></asp:TextBox>
</td>
</tr>
<tr>
<td colspan="2" align="center">
<asp:Button ID="Button1" runat="server" Text="Update Data" Font-Names="Verdana" Width="213px"
BackColor="Orange" Font-Bold="True" OnClick="Button1_Click" />
</td>
</tr>
<tr>
<td colspan="2" align="center">
<asp:Label ID="Label5" runat="server" Font-Bold="true" Font-Names="Verdana"></asp:Label>
</td>
</tr>
</table>
</div>
</center>
</form>
</body>
</html>
Step 4: The complete code of webform1.aspx.cs looks like this:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Xml.Linq;
namespace LINQtoXMLUpdateApp
{
public partial class WebForm1 : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
}
protected void Button1_Click(object sender, EventArgs e)
{
if (string.IsNullOrEmpty(TextBox4.Text) || string.IsNullOrEmpty(TextBox1.Text)|| string.IsNullOrEmpty(TextBox2.Text) || string.IsNullOrEmpty(TextBox3.Text))
{
Label5.Text = "Please Enter Some Values";
Label5.ForeColor = System.Drawing.Color.Red;
}
else
{
XDocument document = XDocument.Load(Server.MapPath("Employee.xml"));
var updateQuery = from r in document.Descendants("Employee")where r.Element("Id").Value == TextBox4.Textselect r;
foreach (var query in updateQuery)
{
query.Element("FirstName").SetValue(TextBox1.Text);
query.Element("LastName").SetValue(TextBox2.Text);
query.Element("Age").SetValue(TextBox3.Text);
}
document.Save(Server.MapPath("Employee.xml"));
Label5.Text = "Data Updated Successfully";
Label5.ForeColor = System.Drawing.Color.Green;
TextBox4.Text = string.Empty;
TextBox1.Text = string.Empty;
TextBox2.Text = string.Empty;
TextBox3.Text = string.Empty;
}
}
}
}
Step 5: The output of the application looks like this:
![update-data-using-linq-to-xml.png]()
Step 6: The data updating to XML output of the application looks like this:
![data-using-linq-to-xml.png]()
Step 7: The data updated to XML looks like this:
<?xml version="1.0" encoding="utf-8"?>
<Employees>
<Employee>
<Id>1</Id>
<FirstName>Vijay</FirstName>
<LastName>Prativadi</LastName>
<Age>26</Age>
</Employee>
<Employee>
<Id>2</Id>
<FirstName>Swetha</FirstName>
<LastName>Prativadi</LastName>
<Age>23</Age>
</Employee>
</Employees>
I hope this article is useful for you.