没有给定一个或多个必需参数的值

Question

我的代码有什么问题。我想要的是，如果我单击 rdbNormal（单选按钮），然后在 cmbBuilding（组合框）中单击 select "A"，则所有 RoomNo 的房间类型为 "normal" 并且将显示建筑物 "A"。这是我的代码

Try
    cn.Open()
    If rdbNormal.Checked = True Then
        Dim DataSet As New DataSet
        Dim DataTable As New DataTable
        Dim DataAdapter As New OleDbDataAdapter("SELECT * FROM RoomTable Where Building = '" & cmbBuilding.Text & "' and RoomType = Normal ", cn)
        DataAdapter.Fill(DataTable)

        If DataTable.Rows.Count > 0 Then
            With cmbRoomNo
                .Items.Clear()
                For i As Integer = 0 To DataTable.Rows.Count - 1
                    .Items.Add(DataTable.Rows(i).Item(3))
                Next
                .SelectedIndex = -1
            End With
        End If
        DataTable.Dispose()
        DataAdapter.Dispose()
    End If

Catch ex As Exception
    MsgBox(ex.Message)
End Try
cn.Close()

Answer 1

在您的查询中您有

... and RoomType = Normal

由于未引用 Normal，因此它被视为参数占位符。如果您想匹配文字值，请在其周围加上引号：

... and RoomType = 'Normal'

没有给定一个或多个必需参数的值

No value given one or more required parameters

ms-access-2010

vb.net-2010