What are the best practices for fromatting a string to submit to a SQL Server? In the past I used code like the following:

Public Function sqlText(ByRef str As String) As String
On Error GoTo ErrHandler


    If IsNull(str) Or Len(str) = 0 Then
        sqlText = "''"
    Else
        sqlText = "'" & str & "'"
    End If

End Function

Is there a better way to handle this now? What about boolean and datetimes?

Thanks,

Jason