问题
Why is this code not valid? Pretty sure it's legit in C /C++
Pseudocode:
String s = Console.ReadLine();
int x = 0;
Int32.TryParse(s, out x) ? Console.WriteLine("Foo") : Console.WriteLine("bar");
回答1:
The ternary operator is used to return values and those values must be assigned.
If you want to invoke void methods in a ternary operator, you can use delegates like this:
String s = Console.ReadLine();
int x = 0;
(Int32.TryParse(s, out x) ? new Action(() => Console.WriteLine("Foo")) : () => Console.WriteLine("bar"))();
回答2:
console.writeline return void.. The conditional operator (?:) returns one of two values depending on the value of a Boolean expression
MSDN
回答3:
As discussed here, in C#, not every expression can be used as a statement.
来源：https://stackoverflow.com/questions/38450938/calling-functions-in-c-sharp-ternary-operator