Question

I have a variable, for example $total1. It has a value from the database, for example 6.

Now I do an SQL query and it gets some numbers from tables. For example this: $subtraction1=5, but it is in a while loop so the second time it could be $subtraction1=10 or something like that. Every time in the while loop the $subtraction_total variable would be $subtraction_total1+$subtraction1, because at the bottom of the page I would like to show the $total minus the $subtraction_total1.

但是,在排第一期间,第一次必须检查一下是否已经存在补贴——总额。我知道有选择这样做,但路不短?

Option 1 is to define the variable $subtraction_total1 before the while loop.

备选案文2是:

(!isset($total_subtraction1)){$total_subtraction1=0;}$total_subtraction1=$total1-$subtraction1;

现在,你认为:选择1:界定1个变量是正确的,但对于大约15个变量,我只是想到的是,是否缩短了;

希望你们理解我,我的英语并不好;-

Answer 1

Define and initialize all your variables before use. I think Option 1 follows logically from that.

Don t试图撰写短、快或小trick的法典。易于阅读和维护的书写代码。

Answer 2

我肯定会提倡在诉讼之前确定变数。如果能够在预选之前实现同样的功能,则在休息室内外重复使用<条码><>发送<>>(或任何其他功能”)是浪费的。

如果你只想界定大量变数,而不必在您的休息之前明确宣布这些变量,那么你可以尝试list<^><><>>docs。或以方案方式在 lo中形成你们的变量。

Answer 3

$sub_total = 0;
while ($sub = mysql_get_row(...)) {
  $sub_total += $sub;
}

这样,你就不必在每一行程中再次执行同样的准则(这是良好做法和良好业绩的明智之举),而且,如果你不产生我的奇克,那么,总合美元的定义是默认价值。

友情链接