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HomeDatabaseMysql Tutorial【机房收费系统】上下机分析

机房收费系统的上下机中,联系的表比较多,分别是:Student表,Online表,Cancelcard表,BasicData表,Line表。表多了关系自然也就会增加,理清思路,才能让后面的学习事半功倍,是一件很锻炼和发掘逻辑能力的工作。 下机之后对消费情况进行计算 上机学生分

机房收费系统的上下机中,联系的表比较多,分别是:Student表,Online表,Cancelcard表,BasicData表,Line表。表多了关系自然也就会增加,理清思路,才能让后面的学习事半功倍,是一件很锻炼和发掘逻辑能力的工作。


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下机之后对消费情况进行计算

上机学生分为两种固定用户和临时用户,他们的区别只是单位时间消费的金额不同,相当于网吧的会员和普通用户。

BasicDate表中设定了收费计算情况的基本信息

准备时间,最少时间,递增时间,两种用户单位消费金额

用datediff函数计算出消费时间,将单位转换为分钟:

txtConsumeTime.Text =Int(DateDiff("n", mrc3.Fields("ondate"),txtOffdate.Text)) + Int(DateDiff("n", mrc3.Fields("ontime"), txtOfftime.Text))

做出如下判断

If 消费时间

不要钱,消费金额为0

Else

If 消费时间

收单位时间的钱

End if

If 消费时间整除递增时间 then

消费金额=(消费时间\递增时间)* 单位金额

Else

消费金额=((消费时间\递增时间)+1)*单位金额(相当于进一法,有利于商家)

End if

End if

单位金额出要对用户进行判断,不同身份的用户单位金额不同。最后将对应的改变的信息,给Line和Student表,并之后在界面上显示出来。下机成功。

这个过程中界面上的操作,最终转变为对表的查,删,改,更。蝴蝶效应,一个数据的变化,后面引起多个表的修改,最后再反馈到界面上,整个学习的过程中,理清思路的逻辑思维能力是这个过程最重要的,锻炼了我们的能力。

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