How To Display Data using ASP.NET 2.0 and VB.NET
This tutorial will show you how to display data using ASP.NET 2.0, a repeater control and VB.NET
The Repeater control is a powerful tool and is easy to use.
First, you will need to import the System.Data.SqlClient namespace.
The System.Data.SqlClient namespace contains the SqlCommand and SqlConnection classes that we need in order to connect to our database and to send an SQL command to it.
| Imports System.Data.SqlClient |
We'll put our code in the Page_Load() event.
When the Page_Load() event fires, a new SqlCommand object is instantiated with our connection string and our command.
Afterwards, we will attempt to connect using the Open() method of our cmd.Connection object. Once it is connected we will attempt to execute the command we specified earlier (in this example "SELECT TOP 5 * FROM EMPLOYEES" in the Northwind db).
If all goes well, we will have the results of our SQL query assigned to the rptrExample's DataSource property. Now all we have to do is call the DataBind() method of our rptrExample to bind the data to the control. The data is now ready to be displayed.
Protected Sub Page_Load(ByVal sender As Object, ByVal e As EventArgs) Handles Me.Load Dim cmd As SqlCommand = New SqlCommand("SELECT TOP 5 * FROM EMPLOYEES", New SqlConnection("Server=localhost;Database=Northwind;Trusted_Connection=True;")) Try cmd.Connection.Open() rptrExample.DataSource = cmd.ExecuteReader() rptrExample.DataBind() cmd.Connection.Close()
cmd.Connection.Dispose() Catch ex As Exception
lblStatus.Text = ex.Message
End Try End Sub
End Class |
We have to add a few tags on the front end of the .aspx page to place where we want the Repeater control to display its bound data. We also specify what part of the data from the data set we would like to display (in this case, "DataItem.firstname"). The front end .aspx page looks something like this:
<table width="600" border="0" align="center" cellpadding="5" cellspacing="1" bgcolor="#cccccc">
<tr>
<td width="100" align="right" bgcolor="#eeeeee" class="header1"> Repeated Employee First Name Data:</td>
<td bgcolor="#FFFFFF"> <asp:Repeater ID="rptrExample" runat="server">
<ItemTemplate>
<br />
<%# DataBinder.Eval(Container, "DataItem.firstname") %>
<br />
</ItemTemplate>
</asp:Repeater> <asp:Label ID="lblStatus" runat="server"></asp:Label></td>
</tr>
</table> |
The flow for the code behind page is as follows.
Imports System
Imports System.Data
Imports System.Configuration
Imports System.Web
Imports System.Web.Security
Imports System.Web.UI
Imports System.Web.UI.WebControls
Imports System.Web.UI.WebControls.WebParts
Imports System.Web.UI.HtmlControls Partial Public Class _Default : Inherits System.Web.UI.Page
Protected Sub Page_Load(ByVal sender As Object, ByVal e As EventArgs) Handles Me.Load Dim cmd As SqlCommand = New SqlCommand("SELECT TOP 5 * FROM EMPLOYEES", New SqlConnection("Server=localhost;Database=Northwind;Trusted_Connection=True;")) Try cmd.Connection.Open() rptrExample.DataSource = cmd.ExecuteReader() rptrExample.DataBind() cmd.Connection.Close()
cmd.Connection.Dispose() Catch ex As Exception
lblStatus.Text = ex.Message
End Try End Sub
End Class |