ASP.Net/ADO.net Database/OleDbConnection

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Read data from OleDbConnection (VB.net)

   <source lang="csharp">

<%@ import Namespace="System.Data" %> <%@ import Namespace="System.Data.Oledb" %> <script language="vb" runat="server"> Sub Page_Load()

 Dim strConnection as String = "Provider=Microsoft.Jet.OLEDB.4.0;"
   strConnection += "Data Source=Northwind.mdb"
   data_src.text = strConnection
 Dim strSQL as string = "SELECT FirstName, LastName FROM Employees"
 Dim strResultsHolder as string
 Dim objConnection as New OledbConnection(strConnection)
 Dim objCommand as New OledbCommand(strSQL, objConnection)
 Dim objDataReader as OledbDataReader
 try
   objConnection.Open()
   con_open.text="Connection opened successfully.
" objDataReader = objCommand.ExecuteREader() Do While objDataReader.Read()=True strResultsHolder +=objDataREader("FirstName") strResultsHolder +=" " strResultsHolder +=objDataREader("LastName") strResultsHolder +="
" Loop objDataReader.Close() objConnection.Close() con_close.text="Connection closed.
" divListEmployees.innerHTML = strResultsHolder catch e as Exception con_open.text="Connection failed to open successfully.
" con_close.text=e.ToString() end try

end Sub </script> <html>

 <body>

Reading data from the connection <asp:label id="data_src" runat="server"/> with the DataReader object.

 <asp:label id="con_open" runat="server"/>
list will go here
 <asp:label id="con_close" runat="server"/>
</body>

</html>

      </source>
   
  


Reading data from the OleDbConnection in C#

   <source lang="csharp">

<%@ Import Namespace="System.Data" %> <%@ Import Namespace="System.Data.OleDb" %> <script Language="c#" runat="server">

 void Page_Load()
 {
   string strConnection = "Provider=Microsoft.Jet.OleDb.4.0;";
   strConnection += @"Data Source="+MapPath("EmployeeDatabase.mdb");
   data_src.Text = strConnection;
   string strSQL = "SELECT FirstName, LastName FROM Employee";
   DataSet objDataSet = new DataSet();
   OleDbConnection objConnection = new OleDbConnection(strConnection);
   OleDbDataAdapter objAdapter = new OleDbDataAdapter(strSQL, objConnection);
   objAdapter.Fill(objDataSet, "Employees");
   DataView objDataView = new DataView(objDataSet.Tables["Employees"]);
   dgNameList.DataSource=objDataView;
   dgNameList.DataBind();
 }

</script> <html>

 <body>

Reading data from the connection <asp:label id="data_src" runat="server"/> to the DataGrid control.

 <asp:datagrid id="dgNameList" runat="server" />
</body>

</html>

      </source>
   
  

<A href="http://www.nfex.ru/Code/ASPDownload/EmployeeDatabase.zip">EmployeeDatabase.zip( 10 k)</a>


Try to connect to access database through OleDbConnection (VB.net)

   <source lang="csharp">

<%@ import Namespace="System.Data" %> <%@ import Namespace="System.Data.Oledb" %> <script language="VB" runat="server">

 Sub Page_Load()
   Dim strConnection as String = "Provider=Microsoft.Jet.OLEDB.4.0;"
   strConnection += "Data Source=C:\NonExistent.mdb"
   data_src.text = strConnection
   Dim objConnection as New OledbConnection(strConnection)
   try
     objConnection.Open()
     con_open.text="Connection opened successfully.
" objConnection.Close() con_close.text="Connection closed.
" catch e as Exception con_open.text="Connection failed to open.
" con_close.text=e.ToString() end try end Sub

</script> <html>

 <body>

Testing the data connection <asp:label id="data_src" runat="server"/>

 <asp:label id="con_open" runat="server"/>
<asp:label id="con_close" runat="server"/>
</body>

</html>

      </source>
   
  


Working with Transactions with OleDbConnection (VB.net)

   <source lang="csharp">

<%@ Page Language=VB Debug=true %> <%@ Import Namespace="System.Data" %> <%@ Import Namespace="System.Data.OLEDB" %> <script runat=server> Sub Page_Load(ByVal Sender as Object, ByVal E as EventArgs)

   Dim DBConn as OleDbConnection
   Dim DBDelete As New OleDbCommand
   Dim DBTrans As OleDbTransaction
   DBConn = New OleDbConnection( _
       "PROVIDER=Microsoft.Jet.OLEDB.4.0;" _
       & "DATA SOURCE=" _
       & Server.MapPath("EmployeeDatabase.mdb;"))
   DBConn.Open()
   DBTrans = DBConn.BeginTransaction()
   DBDelete.Connection = DBConn
   DBDelete.Transaction = DBTrans
   DBDelete.rumandText = "Delete From Employee " _
       & "Where ID = 1"
   DBDelete.ExecuteNonQuery()
   DBDelete.rumandText = "Delete From Employee " _
       & "Where ID = 2"
   DBDelete.ExecuteNonQuery()
   DBTrans.RollBack()
   lblMessage.Text = "No action was taken."
   "DBTrans.rumit()

End Sub </SCRIPT> <HTML> <HEAD> <TITLE>Working with Transactions with an Access Database</TITLE> </HEAD> <Body LEFTMARGIN="40"> <form runat="server">

<asp:label

   id="lblMessage"
   runat="Server"

/> </form> </BODY> </HTML>

      </source>
   
  

<A href="http://www.nfex.ru/Code/ASPDownload/EmployeeDatabase.zip">EmployeeDatabase.zip( 10 k)</a>