C#中枚举类型enum的使用[转载]

enum Fabric
{
Cotton = 1,
Silk = 2,
Wool = 4,
Rayon = 8,
Other = 128
}

根据下面的两个例子，粗略地说，一方面，设置标志[Flags]或者[FlagsAttribute]，则表明要将符号名列举出来；另一方面，可以通过强制转换，将数字转换为符号名。说不准确。看下面的例子体会吧。注意：

例二：
class FlagsAttributeDemo

{

// Define an Enum without FlagsAttribute.

enum SingleHue : short

{

Black = 0,

Red = 1,

Green = 2,

Blue = 4

};

// Define an Enum with FlagsAttribute.

[FlagsAttribute]

enum MultiHue : short

{

Black = 0,

Red = 1,

Green = 2,

Blue = 4

};

static void Main( )

{

Console.WriteLine(

"This example of the FlagsAttribute attribute \n" +

"generates the following output." );

Console.WriteLine(

"\nAll possible combinations of values of an \n" +

"Enum without FlagsAttribute:\n" );

// Display all possible combinations of values.

for( int val = 0; val <= 8; val++ )

Console.WriteLine( "{0,3} - {1}", val, ( (SingleHue)val ).ToString( ) );



Console.WriteLine( "\nAll possible combinations of values of an \n" + "Enum with FlagsAttribute:\n" );

// Display all possible combinations of values.

// Also display an invalid value.

for( int val = 0; val <= 8; val++ )

Console.WriteLine ( "{0,3} - {1}", val, ( (MultiHue)val ).ToString( ) );

}

}

/*

This example of the FlagsAttribute attribute

generates the following output.

All possible combinations of values of an

Enum without FlagsAttribute:

0 - Black

1 - Red

2 - Green

3 - 3

4 - Blue

5 - 5

6 - 6

7 - 7

8 - 8

All possible combinations of values of an

Enum with FlagsAttribute:

0 - Black

1 - Red

2 - Green

3 - Red, Green

4 - Blue

5 - Red, Blue

6 - Green, Blue

7 - Red, Green, Blue

8 - 8

*/