if/else vs ternary operator

2019-01-15 19:33发布

问题:

Considering the evaluation time, are following two equivalent?

if(condition1)
{
    //code1
}
else
{
    //code2
}

condition1 ? code1 : code2

Or they are just syntactically different?

回答1:

The difference is that the latter station can be used to return a value based on a condition.

For example, if you have a following statement:

if (SomeCondition())
{
    text = "Yes";
}
else
{
    text = "No";
}

Using a ternary operator, you will write:

text = SomeCondition() ? "Yes" : "No";

Note how the first example executes a statement based on a condition, while the second one returns a value based on a condition.



回答2:

Well ... In the former case, you can have any amount or type (expression vs statement) of code in place of code1 and code2. In the latter case, they must be valid expressions.



回答3:

Yes & Yes.

Only profit is to save lines of code.



回答4:

Yes, these are two different syntactical forms and will work identically and most likey identical code will be emitted by the compiler.