📄 datareader-jet.aspx
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<%@Page Language="VB"%>
<%@Import Namespace="System.Data" %>
<%@Import Namespace="System.Data.OleDb" %>
<%@ Register TagPrefix="wrox" TagName="connect" Src="..\global\connect-strings.ascx" %>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
<html><head>
<title>The .NET OleDbDataReader and OleDbConnection Objects</title>
<!-- #include file="..\global\style.inc" -->
</head>
<body bgcolor="#ffffff">
<span class="heading">The .NET OleDbDataReader and OleDbConnection Objects</span><hr />
<!--------------------------------------------------------------------------->
<%'-- insert connection string script --%>
<wrox:connect id="ctlConnectStrings" runat="server"/>
<div>Connection string: <b><span id="outConnect" runat="server"></span></b></div>
<div>SELECT command: <b><span id="outSelect" runat="server"></span></b></div>
<div id="outError" runat="server"> </div>
<div id="outResult" runat="server"></div>
<script language="vb" runat="server">
Sub Page_Load()
'declare a string to hold the results as an HTML table
Dim strResult As String = "<table>"
'get connection string from ..\global\connect-strings.ascx user control
Dim strConnect As String
strConnect = ctlConnectStrings.JetConnectionString
outConnect.InnerText = strConnect 'and display it
'specify the SELECT statement to extract the data
Dim strSelect As String
strSelect = "SELECT * FROM BookList WHERE ISBN LIKE '1861003%'"
outSelect.InnerText = strSelect 'and display it
Try
'create a new Connection object using the connection string
Dim objConnect As New OleDbConnection(strConnect)
'open the connection to the database
objConnect.Open()
'create a new Command using the connection object and select statement
Dim objCommand As New OleDbCommand(strSelect, objConnect)
'declare a variable to hold a DataReader object
Dim objDataReader As OleDbDataReader
'execute the SQL statement against the command to fill the DataReader
objDataReader = objCommand.ExecuteReader()
'iterate through the records in the DataReader getting field values
'the Read method returns False when there are no more records
Do While objDataReader.Read()
strResult += "<tr><td>" & objDataReader("ISBN") & "</td><td> " _
& objDataReader("Title") & "</td><td> " _
& objDataReader("PublicationDate") & "</td></tr>"
Loop
'close the DataReader and Connection
objDataReader.Close()
objConnect.Close()
Catch objError As Exception
'display error details
outError.InnerHtml = "<b>* Error while accessing data</b>.<br />" _
& objError.Message & "<br />" & objError.Source
Exit Sub ' and stop execution
End Try
'add closing table tag and display the results
strResult += "</table>"
outResult.InnerHtml = strResult
End Sub
</script>
<!--------------------------------------------------------------------------->
<!-- #include file="..\global\foot.inc" -->
</body>
</html>
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