机房收费系统之结账

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汇总

　　充值表中添加了UserID这个字段，便于在学生注册的时候就将金额相关信息存入充值表中，减少了计算的复杂性。

        '汇总（注意count和sum的区别）
        If SSTab1.Tab = 4 Then
            If comboOpUserID.Text = "" Then     
                MsgBox "请选择操作员用户！", vbOKOnly + vbExclamation, 提示
                Exit Sub
            End If
            '计算售卡张数,少用 count(字段名)，因为它会排除NULL值
            txtSQL = "select * from student_Info where userID = '" & comboOpUserID.Text & "'and Ischeck = '" & "未结账" & "'"
            Set mrc = ExecuteSQL(txtSQL, MsgText)'              
                If mrc.RecordCount = 0 Then
                    txtSellCardSum.Text = 0
                Else
                    txtSellCardSum.Text = mrc.RecordCount  '售卡张数
                End If            
              
            '计算退卡张数
            txtSQL = "select * from CancelCard_Info where userID = '" & comboOpUserID.Text & "'and status = '" & "未结账" & "'"
            Set mrc = ExecuteSQL(txtSQL, MsgText)             
                If mrc.RecordCount = 0 Then
                    txtBackCardSum.Text = 0
                Else
                    txtBackCardSum.Text = mrc.RecordCount '退卡张数
                End If  
              
            '计算充值金额(不区分固定用户还有临时用户）
            txtSQL = "select sum(addmoney) as sum_info from Recharge_Info  where userID = '" & comboOpUserID.Text & "'and status = '" & "未结账" & "'"
            Set mrc = ExecuteSQL(txtSQL, MsgText)
                If IsNull(Trim(mrc.Fields(0))) Then
                    txtRecharge.Text = 0
                Else
                    txtRecharge.Text = mrc.Fields(0)   '括号里需要是0，因为临时表sum_info只有一列
                End If 
              
            '计算退卡金额
            txtSQL = "select sum(CancelCash) as sum_info from CancelCard_Info where userID = '" & comboOpUserID.Text & "'and status = '" & "未结账" & "'"
            Set mrc = ExecuteSQL(txtSQL, MsgText)                
                If IsNull(Trim(mrc.Fields(0))) Then  '为空
                    txtBackCardMoney.Text = 0
                Else
                    txtBackCardMoney.Text = mrc.Fields(0)
                End If
              
            '计算临时收费金额
         
            txtSQL = "select sum(addmoney) as sum_info from Recharge_Info where userID = '" & comboOpUserID.Text & " 'and type = '临时用户' and status = '未结账'"
            Set mrc = ExecuteSQL(txtSQL, MsgText)
                If IsNull(mrc.Fields(0)) Then       '无记录
                    txtTemRecharge.Text = 0
                Else
                    txtTemRecharge.Text = mrc.Fields(0)
                End If
                
                '计算总售卡数
                txtSellCardActual.Text = Val(txtSellCardSum.Text) - Val(txtBackCardSum.Text)
                
                '计算应收金额
                txtCollectMoney.Text = Val(txtRecharge.Text) - Val(txtBackCardMoney.Text)
        End If
                        

sum是对符合条件的记录的数值列求和

count 是对查询中符合条件的结果(或记录)的个数
例如：
表fruit
id     name    price
1     apple     3.00
2     pear       4.00
select count(price) from fruit; ----执行之后结果为：2  (表示有2条记录)
select  sum(price) from fruit;---执行之后结果为：7:00（表示各记录price字段之和为7.00）

结账

'结账分为两部分:
'一是将相关信息存入日结账单中
'二是改变相关表中的结账状态，即将"未结账"改为"已结账"
Private Sub cmdAccount_Click()
    Dim txtSQL As String
    Dim MsgText As String
    Dim mrcS As ADODB.Recordset
    Dim mrcR As ADODB.Recordset
    Dim mrcc As ADODB.Recordset    '退卡
    Dim mrcday As ADODB.Recordset
    Dim mrcL As ADODB.Recordset
    Dim ConsumeCash As Integer   '消费金额中间变量
    Dim sumcash As Integer
    Dim mrc As ADODB.Recordset    'sum的临时表即sum_info
    
    If comboOpUserID.Text = "" Then
        MsgBox "请选择操作员后再结账！", vbOKOnly + vbExclamation, 提示
        Exit Sub
    End If
        
    '计算上期充值卡余额
    txtSQL = "select sum(cash) from student_Info where UserID='" & Trim(comboOpUserID.Text) & "'and ischeck = '" & "未结账" & "'"
    Set mrcS = ExecuteSQL(txtSQL, MsgText)
        If IsNull(mrcS.Fields(0)) Then
            sumcash = 0
        Else
            sumcash = mrcS.Fields(0)
        End If
    
    '从line表计算当日消费金额
    txtSQL = "select sum(consume) from Line_Info "
    Set mrcL = ExecuteSQL(txtSQL, MsgText)
        If IsNull(mrcL.Fields(0)) Then   '为空
            ConsumeCash = 0
        Else
            ConsumeCash = mrcL.Fields(0)
        End If
    
    '将相应的记录存入到日结表
    txtSQL = "select * from CheckDay_Info where UserID='" & Trim(comboOpUserID.Text) & "'and date=' " & Date & "'"
    Set mrcday = ExecuteSQL(txtSQL, MsgText)
    
    '当天结多次账的情况，就在原有基础上更新
    If mrcday.EOF = False Then
        mrcday!RemainCash = sumcash + mrcday!RemainCash
        mrcday!RechargeCash = Val(txtRecharge.Text) + mrcday!RechargeCash                                    
        mrcday!ConsumeCash = ConsumeCash + mrcday!ConsumeCash
        mrcday!CancelCash = Val(txtBackCardMoney.Text) + mrcday!CancelCash
        mrcday!AllCash = (sumcash + Val(txtRecharge.Text) - Val(txtBackCardMoney.Text) - ConsumeCash) + mrcday!AllCash
        mrcday!Date = Date
        mrcday!UserID = comboOpUserID.Text
        mrcday.Update
        mrcday.Close
        mrcS.Close
        mrcL.Close
    Else
        '如果没结过账就添加新记录
        mrcday.AddNew
        mrcday!RemainCash = sumcash
        mrcday!RechargeCash = Val(txtRecharge.Text)   
        mrcday!ConsumeCash = ConsumeCash
        mrcday!CancelCash = Val(txtBackCardMoney.Text)
        mrcday!AllCash = sumcash + Val(txtRecharge.Text) - Val(txtBackCardMoney.Text) - ConsumeCash
        mrcday!Date = Date
        mrcday!UserID = comboOpUserID.Text
        mrcday.Update
        mrcday.Close
        mrcS.Close
        mrcL.Close
    End If
    
'------------------------------------------------------------------------------------------------------------------
    '更新学生表
    txtSQL = "select * from student_Info where UserID='" & Trim(comboOpUserID.Text) & "'and Ischeck = '" & "未结账" & "'"
    Set mrcS = ExecuteSQL(txtSQL, MsgText)
        Do While Not mrcS.EOF
            mrcS!Ischeck = "已结账"
            mrcS.Update
            mrcS.MoveNext
        Loop
    mrcS.Close
    
    '更新充值表
    txtSQL = "select * from Recharge_Info where UserID='" & Trim(comboOpUserID.Text) & "'and status = '" & "未结账" & "'"
    Set mrcR = ExecuteSQL(txtSQL, MsgText)
        Do While Not mrcR.EOF
            mrcR!Status = "已结账"
            mrcR.Update
            mrcR.MoveNext
        Loop
    mrcR.Close
    
    '更新退卡表
     txtSQL = "select * from Cancelcard_Info where UserID='" & Trim(comboOpUserID.Text) & "'and status = '" & "未结账" & "'"
     Set mrcc = ExecuteSQL(txtSQL, MsgText)
        Do While Not mrcc.EOF
           mrcc!Status = "已结账"   
           mrcc.Update
           mrcc.MoveNext
        Loop
     mrcc.Close
     
     MsgBox "结账成功！", vbOKOnly + vbExclamation, "提示"
     
'------------------------------------------------------------------------------------------------------------------
    '清空文本框显示的信息
        Dim ctr1 As Control
        For Each ctr1 In Me.Controls
            If TypeOf ctr1 Is TextBox Then
                ctr1.Text = ""
            End If
        Next
    
    Unload Me
End Sub

　　日结账单添加了UserID这个选项，便于查看是谁结的账

　　上下机请见：机房收费系统之纵观全局