ASP.Net/ADO.net Database/OleDbConnection
Содержание
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"/>
<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>