c# - 什么时候需要数字后缀 L(长)？

Question

我知道像 1.5 这样的东西是 double 的，所以你需要使用 m 后缀将其分配给小数。

decimal d = 1.5; // won't compile
decimal d = 1.5m; // will compile

现在，像 0 这样的文字是一个 int。但是为什么我只能把它分配给一个long呢？将 0 与 0L 分配给 long 类型的变量之间有什么区别吗？

long l = 0;
long l = 0L;

Answer 1

But why can I just assign it to a long?

11.2.3 the spec状态:

Implicit numeric conversions
The implicit numeric conversions are:
•   From sbyte to short, int, long, float, double, or decimal.
•   From byte to short, ushort, int, uint, long, ulong, float, double, or decimal.
•   From short to int, long, float, double, or decimal.
•   From ushort to int, uint, long, ulong, float, double, or decimal.
•   From int to long, float, double, or decimal.
•   From uint to long, ulong, float, double, or decimal.
•   From long to float, double, or decimal.
•   From ulong to float, double, or decimal.
•   From char to ushort, int, uint, long, ulong, float, double, or decimal.
•   From float to double.
Conversions from int, uint, long, or ulong to float and from long or ulong to double may cause a loss of precision, but will never cause a loss of magnitude. The other implicit numeric conversions never lose any information.

从 int 到 long、float、double 或 decimal。 是此处的相关项。 0默认是int，所以可以隐式转换成long。

Is there any difference between assigning 0 versus 0L to a variable of type long?

它们的行为完全相同。 IL 完全相同。