从 Vb.net 更新数据库日期/时间格式时出错

Question

我正在使用用 VB.Net 编写的更新查询，然后将其发送到 SQLite 客户端。更新时一切正常，日期除外。我在 VB 表单上有 2 个日期/时间选择器。我在那里取值并将它们向左修剪，10 所以我只有日期并将其放入变量中。然后我把它放在一个查询中，它应该发送到数据库客户端。而不是输入日期，它会擦除​​值并将其留空！知道为什么会这样吗？代码如下！

Sub Cmd_SaveClick(sender As Object, e As EventArgs)
    'Create checkbox text

    DOB_DTP = Microsoft.VisualBasic.Left(dtp_DOB.Value, 10)
    DBS_DTP = Microsoft.VisualBasic.Left(dtp_DBS.Value, 10)

    'DBS
    If cb_DBS.Checked = True Then
        DBS = "T"
    Else
        DBS = "F"
    End If

    'MONDAY
    If CB_Monday.Checked = True Then
        Monday = "T"
    Else
        Monday = "F"
    End If

    'TUESDAY
    If CB_Tuesday.Checked = True Then
        Tue = "T"
    Else
        Tue = "F"
    End If

    'WEDNESDAY
    If CB_Wednesday.Checked = True Then
        Wed = "T"
    Else
        Wed = "F"
    End If

    'THURSDAY
    If CB_Thursday.Checked = True Then
        Thur = "T"
    Else
        Thur = "F"
    End If

    'FRIDAY
    If CB_Friday.Checked = True Then
        Fri = "T"
    Else
        Fri = "F"
    End If

    'Update into Database
    SQLcommand = SQLconnect.CreateCommand

    SQLcommand.CommandText = "UPDATE Staff SET Staff_Surname = '" & txt_Surname.Text & "' , Staff_First_Name = '" & txt_Firstname.Text & "' , Staff_DOB = '" & DOB_DTP & "' , Staff_Contact_No_1 = '" & txt_Contact_1.Text & "' , Staff_Contact_No_2 = '" & txt_Contact_2.Text & "', Staff_Email = '" & txt_email.Text & "' , DBS_Check = '" & DBS & "' , DBS_Renew_Date = '" & DBS_DTP & "' , Work_Monday = '" & Monday & "' , Work_Tuesday = '" & Tue & "' , Work_Wednesday = '" & Wed & "' , Work_Thursday = '" & Thur & "' , Work_Friday = '" & Fri & "' WHERE Username = '"  & Change_Password.Password.usernamechange & "'"

    SQLcommand.ExecuteNonQuery()

    SQLcommand.Dispose()

    MsgBox("Saved!",vbInformation,"Saved!")

End Sub

Answer 1

我强烈建议您使用 SqlParameters 构建命令。

mySqlcommand.CommandText = "UPDATE [TABLENAME] SET [COLUMN1] = @COLUMN1, [COLUMN2] = @COLUMN2 WHERE [ID] = @ID;"
mySqlcommand.Parameters.Add(New SqlParameter("@COLUMN1", DBNull.Value))
mySqlcommand.Parameters.Add(New SqlParameter("@COLUMN2", DBNull.Value))
mySqlcommand.Parameters.Add(New SqlParameter("@ID", 1))

然后，API 将处理所有格式。