User control is powerful functionality of ASP.NET. With the help of the user control you can reuse the Design as well as code in the application. Developing User control is similar to developing form in ASP.NET. User control is created in markup file with .ascx extension.
We create two user control one for collect the user information and second for Display the user information.
Step 1: Add the Web user control in your form with the name UserInformation.ascx and UserInformationGrid.ascx.
Step 2: Add the code in Userinformation.ascx
<%@ Control Language="C#"
AutoEventWireup="true"
CodeFile="UserInformation.ascx.cs" Inherits="UserControl_UserInformation"
%>
<table align="center">
<tr>
<td colspan="2">
<asp:Label ID="lblusername"
runat="server"
ForeColor="Red"></asp:Label>
</td>
</tr>
<tr>
<td>
UserName:
</td>
<td>
<asp:TextBox ID="txtusername"
runat="server"></asp:TextBox><asp:RequiredFieldValidator
ID="RequiredFieldValidator1"
runat="server"
ControlToValidate="txtusername">*</asp:RequiredFieldValidator>
</td>
</tr>
<tr>
<td>
</td>
<td>
<asp:Button ID="btnSaveName"
runat="server"
Text="Save"
OnClick="btnSaveName_Click"
style="height: 26px" />
</td>
</tr>
</table>
In Userinformation.ascx.cs file add the code like this.
using System;
using System.Collections;
using System.Configuration;
using System.Data;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.HtmlControls;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Linq;
public partial class UserControl_UserInformation
: System.Web.UI.UserControl
{
protected void
Page_Load(object sender, EventArgs e)
{
if (!IsPostBack)
{
}
}
protected void
btnSaveName_Click(object sender, EventArgs e)
{
InsertData();
Response.Redirect("~/Default.aspx");
}
private void
InsertData()
{
Userinfo info = new
Userinfo();
info.UserName =
txtusername.Text.Trim();
using (UserInformationDataContext
db = new UserInformationDataContext())
{
try
{
db.Userinfos.InsertOnSubmit(info);
db.SubmitChanges();
}
catch (Exception
ex)
{
Response.Write("Error:" +
ex.Message);
}
}
}
}
Step 3: Add the code in UserInformationGrid.ascx.
<%@ Control Language="C#"
AutoEventWireup="true"
CodeFile="UserInformationGrid.ascx.cs"
Inherits="UserControl_UserInformationGrid"
%>
<asp:GridView ID="GridView1"
runat="server"
AllowPaging="True"
AutoGenerateColumns="False">
<Columns>
<asp:BoundField DataField="ID"
HeaderText="ID"
/>
<asp:BoundField DataField="UserName"
HeaderText="UserName"
/>
</Columns>
</asp:GridView>
UserInformationGrid.ascx.cs add
using System;
using System.Collections;
using System.Configuration;
using System.Data;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.HtmlControls;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Linq;
public partial class UserControl_UserInformationGrid
: System.Web.UI.UserControl
{
protected void Page_Load(object
sender, EventArgs e)
{
if(!IsPostBack)
{
using(UserInformationDataContext
db = new UserInformationDataContext())
{
var info = from p in db.Userinfos
select new
{
p.ID,
p.UserName
};
if (info != null)
{
GridView1.DataSource = info;
GridView1.DataBind();
}
}
}
}
}
Step 4: To add the user control in your page you must add tag
<%@ Register%> . it contain src,TagName,TagPrefix
Your code in the your aspx file like this.
<%@ Page Language="C#"
AutoEventWireup="true" CodeFile="Default.aspx.cs" Inherits="_Default" %>
<%@ Register src="~/UserControl/UserInformation.ascx"
TagName="UserInformation"
TagPrefix="UserInformation"
%>
<%@ Register src="UserControl/UserInformationGrid.ascx"
tagname="UserInformationGrid"
tagprefix="uc1"
%>
<!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 runat="server">
<title>Untitled Page</title>
</head>
<body>
<form id="form1" runat="server">
<div>
<table>
<tr>
<td valign="top">
<UserInformation:UserInformation id="UserInformation"
runat="server"/>
</td>
<td>
<uc1:UserInformationGrid
ID="UserInformationGrid1"
runat="server"
/>
</td>
</tr>
<tr>
<td>
<asp:PlaceHolder ID="_placeHoldaer"
runat="server"></asp:PlaceHolder>
</td>
</tr>
</table>
</div>
</form>
</body>
</html>
Step 5: Build the application and run the project.
Conclusion:
In this article we have seen how to create user control and how to use it in our web forms.