Enumerations are a method of grouping constant values. For example:
enum suits { clubs, diamonds, spades, hearts };
By default, the first constant is assigned the value 0 and all subsequent values increment by 1. However, you can assign any value to any constant -- the automatic increments will continue from that point.
enum suits { clubs = 1, diamonds, spades, hearts };
You can also assign the same value to multiple constants.
enum suits { clubs = 1, diamonds, spades = 1, hearts };
By grouping constants within enumerations your code becomes more secure because you cannot pass constant literals into functions that expect an enumeration. Consider the following:
void print_suit(unsigned id)
{
switch (id)
{
case (0): std:cout << "Clubs"; break;
case (1): std:cout << "Diamonds"; break;
case (2): std:cout << "Spades"; break;
case (3): std:cout << "Hearts"; break;
default: std::cout << "Invalid";
}
}
In the above example there is nothing to prevent the caller from passing an invalid value, such as 42, which the function caters for with a default case. However, by passing an enum instead, invalid values are completely eliminated:
void print_suit(suits suit)
{
switch (suit)
{
case (clubs): std:cout << "Clubs"; break;
case (diamonds): std:cout << "Diamonds"; break;
case (spades): std:cout << "Spades"; break;
case (hearts): std:cout << "Hearts";
}
}
The enum keyword means enumeration.
You can't pass an enum as an argument to a function. An enum in C isn't an object, it's a type. All you can do is pass a variable that is of the particular enum's type.
In C++, enum signifies a slightly stronger type than in C. For example, in C, one could write: enum Direction { UP, DOWN }; Direction d = 1; In C++, this would be illegal, only UP or DOWN can be assigned to a variable of type Direction, though there is still implicit casting to integer, so one could still write: int i = UP; Another difference has to do with the way variable are declared in general in C++. In C, once the enum was declared as above, declaring variables of type Direction would have to be done through the enum keyword, like this: enum Direction d = UP; In C++, the name "Direction" becomes a type in itself, so you can write: Direction d = UP;
That is correct - In c plus plus you cannot assign integer value to enum - You can only assign an enum value to an enum. Even though an enum looks like an integer, it is not. It is an enum, and C++ implements strict type checking to reduce the probability of bad programming practices. enum ColorCode {black, brown, red, orange, yellow, green, blue, violet, grey, white}; ColorCode myColorCode; myColorCode = yellow; Even though yellow has an integer value of 4, you cannot say myColorCode = 4.
enum, void and const are relatively new keywords in Cnew, on the other hand, isn't a keyword in C
The enum keyword means enumeration.
You can't pass an enum as an argument to a function. An enum in C isn't an object, it's a type. All you can do is pass a variable that is of the particular enum's type.
In C++, enum signifies a slightly stronger type than in C. For example, in C, one could write: enum Direction { UP, DOWN }; Direction d = 1; In C++, this would be illegal, only UP or DOWN can be assigned to a variable of type Direction, though there is still implicit casting to integer, so one could still write: int i = UP; Another difference has to do with the way variable are declared in general in C++. In C, once the enum was declared as above, declaring variables of type Direction would have to be done through the enum keyword, like this: enum Direction d = UP; In C++, the name "Direction" becomes a type in itself, so you can write: Direction d = UP;
That is correct - In c plus plus you cannot assign integer value to enum - You can only assign an enum value to an enum. Even though an enum looks like an integer, it is not. It is an enum, and C++ implements strict type checking to reduce the probability of bad programming practices. enum ColorCode {black, brown, red, orange, yellow, green, blue, violet, grey, white}; ColorCode myColorCode; myColorCode = yellow; Even though yellow has an integer value of 4, you cannot say myColorCode = 4.
enum, void and const are relatively new keywords in Cnew, on the other hand, isn't a keyword in C
all the three are user defined datatypes
Kadhal Enum Nadhiyinile was created in 1989.
An enum type is a type whose fields consist of a fixed set of constants
Here is the simple code, which demonstrates how you can use enum as function argument in c. =================================================== #include <stdio.h> // Enum declaration for power stat enum PowerStat{ OFF, ON } powerStat; // Function printing the stat of power supply void func( enum PowerStat ); int main(int argc, char* argv[]) { // Set power supply stat OFF powerStat = OFF; // Call function to print the stat func( powerStat); // Set power supply stat ON powerStat = ON; // Call function to print the stat func( powerStat); return 0; } void func( enum PowerStat stat) { printf("Power is = %s\n", stat ? "ON" : "OFF" ); } ================================================== I haven't compiled and run above code but it has to work fine. Let me know, if you found difficulty to compile it. Email: ramji.jiyani@gmail.com
An enum, short for enumerated type, is a variable type that can only take on the values that are declared inside the enum declaration. An enum is declared like a class, except the word "class" is replaced by the word "enum", and the class body is replaced by a list of values that a variable of that type can take on. You can also include methods, instance variables, and constructors in an enum.
Enum in C#, most of time, are used to defined integer-based values in symbolic ways.Example - exiting or return codesTraditionally, when a program exits, it may return an integer value to indicate the status of the execution.0 everything is OK1 Something was wrong, but not fatal2 Fatal Errorpublic enum ExitCode {OK = 0, Warning = 1, FatalError = 2}... return ExitCode.OK; // old way would by return 0; and one would need to know 0 stands for
Enum in java is a keyword which is introduced in JDK 1.5 and its a type like Interface and Class.Enum constants are implicitly static and final and you can not change there value once created. Enum in Java provides type-safety and can be used inside switch statment like int variables. Since enum is a keyword you can not use as variable name and since its only introduced in JDK 1.5 all your previous code which has enum as variable name will not work and needs to be refactored.