问题
So, I just want to know if its possible to slip in any code or a ternary operator inside the termination bit of a for loop. If it is possible, could you provide an example of a ternary operator in a for loop? Thanks!
for (initialization; termination; increment) {
statement(s)
}
回答1:
The termination clause in the for statement (if supplied - it's actually optional) can be any expression you want so long as it evaluates to a boolean.
It must be an expression, not an arbitrary code block.
回答2:
Yes you can since only thing here is termination should be a boolean
for (int i=0; i==10?i<5:i<6; i++) {
}
But what is the point of this?
Things to remember. Termination condition of a for loop should be a boolean
回答3:
Absolutely, it is possible:
for (int i = 0 ; i < someCondition ? first : second ; i++) {
...
}
you can use ternary operators or any expressions in all three parts of the loop header:
for (int i = flag ? a : -a ; i != (flag ? 2*b : -2*b) ; i += flag ? 1 : -1 ) {
...
}
If you need to insert more complex logic into the termination condition, a good approach would be to define a method: it usually improves readability of your loop:
boolean checkCondition(int i) {
...
}
...
for (int i = 0 ; checkCondition(i) ; i++) {
...
}
回答4:
The termination part of the for loop requires a boolean condition. You can pass anything that gives a boolean value for the termination part.
For ex:
for (int i = 0; i<5?true:false; i++)
{
}
来源：https://stackoverflow.com/questions/26158515/is-it-possible-to-fit-in-a-ternary-operator-as-the-termination-in-a-for-loop