ASP.Net/ADO.net Database/Exception

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Catch database operation exceptions for data binding

   <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:\Northwind.mdb"
   data_src.text = strConnection
 Dim strSQL as string = "SELECT FirstName, MiddleName, LastName FROM Employees;"
 Dim objDataSet as new DataSet()
 Dim objConnection as new OledbConnection(strConnection)
 Dim objAdapter as new OledbDataAdapter(strSQL, objConnection)

Try 

 objAdapter.Fill(objDataSet, "Employees")
 
 Dim objDataView as New DataView(objDataSet.Tables("Employees"))
 
 dgNameList.DataSource=objDataView
 dgNameList.DataBind()

Catch objError as OledbException 

 If Left(objError.Message,21)="Login failed for user" Then 
   divErrorReport.InnerHTML = "Problem with Log-in"
 ElseIf Left(objError.Message,19)="Could not find file" Then 
   divErrorReport.InnerHTML = "We could not find the MDB file that you asked for"
 Else
   divErrorReport.InnerHTML =  "
message - " & objError.Message
   divErrorReport.InnerHTML += "
source - " & objError.Source
 End If

End Try end Sub </script> <html> 

 <body>

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

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

 </body>

</html> 

      </source>
Источник — «http://www.nfex.ru/index.php?title=ASP.Net/ADO.net_Database/Exception&oldid=1631»