vba ：只在每个循环的第一个上做一些事情
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vba : do something only on the first for each loop
提问by l--''''''---------''''''''''''
for each element in sarray
if ... then
if this is the first time the above IF statenent was executed ... then
end if
next element
i want to do something ONLY the first time that the first IF THENstatement is executed. i am having a lot of problems with my logic. please help!
我只想在第一次IF THEN执行第一条语句时做一些事情。我的逻辑有很多问题。请帮忙！
回答by cdeutsch
var isExecuted = false
for each element in sarray
if ... then
if Not isExecuted Then
--do stuff
isExecuted = true
end if
end if
next element
回答by Dr. belisarius
flag = true
For each ...
if flag
do whatever with first element
flag = false
endif
do what you want with all elements ... including the first
next
回答by user472875
There is probably a better way of doing this but you can have a boolean variable first_time which will start out as true and get set to false in the if statement. You can then check
可能有更好的方法来做到这一点，但你可以有一个布尔变量 first_time ，它开始为真，并在 if 语句中设置为假。然后你可以检查
If first_time = True Then
Stuff
End If
回答by Wodzu
If I understand you correctly you have N elements, and you want to perform some operation only for the first element. So doing this like you want to do is waste of processor time.
如果我理解正确，您有 N 个元素，并且您只想对第一个元素执行某些操作。所以像你想做的那样做是浪费处理器时间。
So I would suggest to rewrite your logic without introducing a new boolean variable. It's cleaner and faster. Something like this for example:
所以我建议在不引入新的布尔变量的情况下重写你的逻辑。它更干净、更快。例如这样的事情：
Dim intCount As Integer
If (some condition) Then
DoSomething with sarray(0)
For intCount = 1 To sarray.Length
//Do something
Next intCount
