如果声明与?和: [英] If statement with ? and :
问题描述
我听说在C
$ b $中使用?
和:
的If语句b我不知道如何使用它,也找不到任何东西。
我需要使用它来缩短我的代码
,我们将不胜感激。
I heard about a kind of If statement which use ?
and :
in C
I dont know how to use it and I cant find anything about it.
I need to use it in order to shorten my code
any help would be appreciated.
推荐答案
?:
是三元运算符 C(也称为条件运算符)。您可以缩短代码,例如
?:
is ternary operator in C (also called conditional operator). You can shorten your code like
if(condition)
expr1;
else
expr2;
至
condition ? expr1 : expr2;
查看其工作原理:
第一个操作数被求值;在它的评估与第二个或第三个操作数的
评估(无论哪个被评估)之间存在一个序列点。仅当第一个操作数比较不等于0
时,才对第二个操作数
求值;仅当第一个操作数等于0
时,才对第三个操作数求值;结果是第二个或第三个操作数
的值(以评估为准),
The first operand is evaluated; there is a sequence point between its evaluation and the evaluation of the second or third operand (whichever is evaluated). The second operand is evaluated only if the first compares unequal to
0
; the third operand is evaluated only if the first compares equal to0
; the result is the value of the second or third operand (whichever is evaluated),
这篇关于如果声明与?和:的文章就介绍到这了,希望我们推荐的答案对大家有所帮助,也希望大家多多支持IT屋!