c语言枚举类型举例（C language enumeration type example）.doc

c语言枚举类型举例（C language enumeration type example） Note: the execution environment for all of the following code is VC++ 6 The difference between macros and enumerations The main difference between macro and enumeration in different periods and stored in the form of action, is to replace the macro work in the pretreatment stage of the text, it replaced the code, running process - no longer exists. Enumeration does not work until the program is running. Enumeration constants are stored in the static storage section of the data segment. Macros take up space in the code segment, and enumerations consume CPU resources in addition to space occupation. But also can not say good than if you need to enumerate the macro definition is very much, with a constant, enum is more obvious than..} {... A lot of define more clearly, the enumeration is also used to define some special types, such as Bool, Such as: type, enum, {FALSE, TRUE}, Bool; In the program, you may need to define an alias for some integers. We can do this by using the preprocessing instruction #define. Your code might be: #define MON 1 #define TUE 2 #define WED 3 #define THU 4 #define FRI 5 #define SAT 6 #define SUN 7 Here, we define a new data type that we hope will do the same. This new data type is called enumeration. 1. define a new data type - enumeration type The following code defines this new data type - enumeration type Enum DAY { MON=1, TUE, WED, THU, FRI, SAT, SUN }; (1) an enumerated type is a collection, and the elements in the collection (enumeration members) are named integer constants, separated by commas. (2) DAY is an identifier that can be considered as the name of the collection, and is an optional, optional item. (3) the default value of the first enumerator member is 0 of the integer, and the value of the subsequent enumeration member is 1 on the previous member. (4) you can set the values of enumerated members artificially so that you can customize an integer in a range. (5) enumerated type is