Updating Records in Database
ASP.NET 2.0 makes it easy to create pages that allow a user to modify values in a database. The ease derives from the capabilities that are built into the data source and data-bound controls.
- Data source controls have a built-in capability to modify data. You've already read about some built-in capabilities, such as sending a SELECT command to the database. ASP.NET 2.0 data source controls also have three capabilities to modify data: update, insert, and delete.
- Data source controls have properties to enable the capability to modify data. The modification capabilities listed in the last point can be turned on or off.
- Data-bound controls can automatically use capabilities that have been turned on in the data source control.Smart data-bound controls “know” which capabilities are turned on for their data source control. However, this sensing is only for smart controls: GridView , DetailsView , and FormView .
- Data-bound controls have properties that enable use of their source control capability. The modification interface can be turned on or off by enabling smart data-bound controls to display options such as Edit or Delete.
Example: Demonstrate Updating record in the database.
UpdatingRecords.aspx
<% @ Page Language ="C#" AutoEventWireup ="true" CodeFile ="UpdatingRecords.aspx.cs" Inherits ="UpdatingRecords" %>
<! 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">
</head >
<body >
<form id ="form1" runat ="server">
<div >
<strong >< em > Updating Record in the Database < br />
<br />Product Name :
<asp:DropDownList ID ="ddlProductName" runat ="server" AutoPostBack ="True">
</asp:DropDownList>
<br />
<br />Updated Product Name:
<asp:TextBox ID ="txtUpdatedPName" runat ="server"></asp:TextBox>
<br />
<br />
<asp:Button ID ="btnUpdate" runat ="server" OnClick ="btnUpdate_Click" Text ="Update Record !!!" />
<br/>
</em></strong>
</div >
</form >
</body >
</html >
UpdatingRecords.aspx.cs
using System;
using System.Data;
using System.Configuration;
using System.Collections;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;
using System.Data.SqlClient;
public partial class UpdatingRecords : System.Web.UI. Page
{
protected void Page_Load( object sender, EventArgs e)
{
if (!IsPostBack) {
//Binding the data with the drop down list.
String strConn = "Data Source=localhost;Initial Catalog=northwind;user id=sa;pwd=sa" ;
//Instantiating Command Object.
SqlConnection conn = new SqlConnection (strConn);
SqlDataAdapter ada = new SqlDataAdapter ( "select * from products" , conn);
DataSet dstProducts = new DataSet ();
ada.Fill(dstProducts);
ddlProductName.DataSource =dstProducts.Tables[0].DefaultView;
ddlProductName.DataTextField = "productName" ;
ddlProductName.DataValueField = "productId" ;
ddlProductName.DataBind();
}
}
protected void btnUpdate_Click( object sender, EventArgs e)
{ //Update Record in the Database.
String strConn = "Data Source=localhost;Initial Catalog=northwind;user id=sa;pwd=sa" ;
//Instantiating Command Object.
SqlConnection conn = new SqlConnection (strConn);
SqlCommand cmd = new SqlCommand ();
cmd.Connection = conn;
string strQuery = "Update products set ProductName = @ProductName where ProductId= @ProductId" ;
cmd.CommandText = strQuery;
cmd.CommandType = CommandType .Text;
//Adding Parameters to the Command Object.
cmd.Parameters.AddWithValue( "@ProductName" ,
txtUpdatedPName.Text);
cmd.Parameters.AddWithValue( "@ProductId" ,ddlProductName.SelectedValue);
//Connection Object Open
conn.Open();
cmd.ExecuteNonQuery();
//Connection Object Closed
conn.Close();
Response.Write( "Updated One Record in the Database Successfully !!!!" );
}
}
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