问题
decimal d = 2;
int i = (int) d;
I've seen this several times in which parentheses are wrapped around data types.
Why not just use int i = int d;?
回答1:
The usage of (int) is called casting (or, type-casting). It is essentially telling that, interpret convert the value of d as to an int (integer) and store it into i.
In other words, it is a way of converting a type to another one (subject to validity of the conversion).
BTW, int i = int d;, as is, is not a valid statement.
回答2:
You're casting d to type int from type decimal. This happens in other languages as well that use static typing.
回答3:
It is a way of converting data type from one type to another using cast operator, usage is as follows:
- (result data type) expression to be converted
来源：https://stackoverflow.com/questions/30790649/in-c-why-are-there-parentheses-around-int-in-this-example