Access Query With Parameters in Visual Studio
Microsoft Access queries with somecolumnname = [?]
do not show up in the list of Views in the New开发者_Python百科 DataSource Wizard in Visual Studio.
The query works perfectly from within Microsoft Access by just prompting for the values of the parameters.
The columns of the query should populate labels on my form based on the values in a couple textboxes.
What is the "best-practices" way to use parameter queries in my .NET application?
Note: If applicable, VB.NET answers preferred over C# (both acceptable).
What if you do this:
somecolumnname = ?
instead of
somecolumnname = [?]
Take a look at this:
Paremeters in TableAdapter not accepted
Are you missing some step?
How to: Connect to Data in an Access Database
Walkthrough: Connecting to Data in an Access Database (Windows Forms)
This is based on a little understanding of Access, not of VB.Net, but it may help.
Dim cn As New OleDb.OleDbConnection
Dim cmd As New OleDb.OleDbCommand
Try
cn.ConnectionString = "Provider=Microsoft.Jet.OLEDB.4.0;" & _
"Data Source=c:\Docs\Test.mdb;"
cn.Open()
cmd.Connection = cn
''It is just a query, not a procedure, but this is what
''works with Access
cmd.CommandType = CommandType.StoredProcedure
cmd.CommandText = "test"
With cmd.Parameters
.AddWithValue("myparam", "SomeVal")
End With
<...>
OLE DB Providers: http://www.carlprothman.net/Default.aspx?tabid=87#OLEDBProviderForMicrosoftJet
精彩评论