c ++ enum

enumerate

  • Constants can be used to create a symbol, instead const.
enum spectrum {
    red, orange, yellow, green, blue, violet, indigo, ultraviolet
};
  • spectrum for the new type. The red, orange or the like as a symbolic constant. Their corresponding value of 0 to 7.
  • By default, the integer assigned to enumerate the amount of default from zero.
  • spectrum band = 2000; // This statement will fail
  • spectrum band = blue; // should this assignment
  • ++ band; // This statement does not make sense
  • band = red + orange; // This statement does not make sense
  • Enumeration amount is an integer, it can be promoted to int. But it can not be automatically converted to int enumeration type.
  • band = 3; // This statement results in the wrong type, but depending on the implementation
  • If the value is valid int enumerated type, it can be cast, convert it to an enumerated type.
  • Enumeration is often used to define symbolic constants, rather than defining a new type.
  • Assignment operator can use explicit assignment.
enum bits{ one = 1, two = 2, four = 4, eight = 8};
  • You can create multiple enumeration values ​​for the same amount.
  • c ++ previous version can only be assigned to enumerate int amount, even now you can use long long long.
  • Enumeration of the range, a little do not understand.

Guess you like

Origin www.cnblogs.com/yangzixiong/p/11960752.html