如何使用vb.net 2010从Access 2007数据库中检索datetime（仅限日期类型）？

Question

我的要求是让用户从DateTimePicker中选择一个日期，然后GataGridView将检索并显示与DateTimePicker中的值匹配的信息。

 Private Sub DateTimePicker3_ValueChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles DateTimePicker3.ValueChanged
    dailyloadglog()
End Sub

Public Sub dailyloadglog()
    Dim connection As New OleDbConnection("Provider=Microsoft.ACE.OLEDB.12.0;Data Source='" & aaa & "';Persist Security Info=True;")
    Try
        Dim OOL As String = "SELECT Glogtbl.DIN, Glogtbl.clock, Int([clock]) AS JustDate, [clock]-Int([clock]) AS JustTime FROM Glogtbl WHERE JustDate = " & DateTimePicker3.Value.ToShortDateString & ""
        Dim cmd As New OleDbCommand
        Dim odpt As New OleDbDataAdapter
        Dim tbl As New DataTable
        With cmd
            .CommandText = OOL
            .Connection = connection
        End With
        With odpt
            .SelectCommand = cmd
            .Fill(tbl)
        End With
        DataGridView4.Rows.Clear()
        For i = 0 To tbl.Rows.Count - 1
            With DataGridView4
                .Rows.Add(tbl.Rows(i)("DIN"), tbl.Rows(i)("clock"), tbl.Rows(i)("JustDate"), tbl.Rows(i)("JustTime"))
            End With
        Next
        connection.Close()
    Catch ex As Exception
        MsgBox(ex.Message)
    End Try
End Sub

ex.exception给了我这个：

当我尝试检索所有日期/时间列时，结果显示：

 Dim OOL As String = "SELECT Glogtbl.DIN, Glogtbl.clock, Int([clock]) AS JustDate, [clock]-Int([clock]) AS JustTime FROM Glogtbl"

JustDate值仍然是格式长日期时间值。因此，与datetimepicker.value进行比较的值总是错误的。最终找不到任何东西!!!

谁可以指导我这个？！

Answer 1

不要使用字符串连接将值插入SQL代码中。始终使用参数。这样做可以避免您遇到的错误分隔符或格式设置等问题。 E.g。

myCommand.CommandText = "SELECT * FROM MyTable WHERE MyColumn = @MyColumn"
myCommand.Parameters.AddWithValue("@MyColumn", myValue)

有很多地方可以找到有关ADO.NET参数的更多信息，例如

http://jmcilhinney.blogspot.com.au/2009/08/using-parameters-in-adonet.html