关于enum应用的总结
/// 枚举绑定--基础方法
/// </summary>
/// <param name="ddlList"></param>
public void LogTypeBind(DropDownList ddlList, string strInfo,Type type)
{
ddlList.Items.Clear();
if (strInfo.Length > 0)
{
ListItem list1 = new ListItem(strInfo, "");
ddlList.Items.Add(list1);
}
//Type type = typeof(temp);
//Type type = temp.GetType();
FieldInfo[] fields = type.GetFields();
int count = fields.Length;
//ddlList.Items.Clear();
for (int i = 1; i < count; i++)
{
FieldInfo field = fields[i];
ListItem list = new ListItem(field.Name, Convert.ToString(i - 1));
ddlList.Items.Add(list);
}
}
以下为参考
出处:http://blog.csdn.net/fanweiwei/archive/2006/09/01/1153172.aspx
/// 新闻、下载资源等的审核状态
/// </summary>
public enum ApplyStatus
{
/// <summary>
/// 审核不通过
/// </summary>
NotPassed = - 1 ,
/// <summary>
/// 未审核
/// </summary>
NotApply = 0 ,
/// <summary>
/// 审核通过
/// </summary>
Passed = 1
}
int fabNum = ( int )status; // 转换为常数值。必须使用强制转换。
ApplyStatus statusString = (ApplyStatus) 1 ; // 常数值转换成符号名。如果使用ToString()，则是((ApplyStatus)1).ToString()，注意必须有括号。
string applyType = status.ToString(); // 显示符号名
string applyVal = status.ToString( " D " ); // 显示常数值
{
Console.WriteLine(s);
}
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：
Console.WriteLine("MyFabric = {0}", fab);//输出：Fabric.Cotton | Fabric.Rayon | Fabric.Silk;
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
*/
public static double GetPrice(Fabric fab)
{
switch (fab)
{
case Fabric.Cotton: return (3.55);
case Fabric.Silk: return (5.65);
case Fabric.Wool: return (4.05);
case Fabric.Rayon: return (3.20);
case Fabric.Other: return (2.50);
default: return (0.0);
}
}
6、上面三点一个完整的例子
//1、enum的定义
public enum Fabric : short
{
Cotton = 1,
Silk = 2,
Wool = 3,
Rayon = 8,
Other = 128
}
//将枚举作为参数传递
public static double GetPrice(Fabric fab)
{
switch (fab)
{
case Fabric.Cotton: return (3.55);
case Fabric.Silk : return (5.65);
case Fabric.Wool: return (4.05);
case Fabric.Rayon: return (3.20);
case Fabric.Other: return (2.50);
default: return (0.0);
}
}
public static void Main()
{
Fabric fab = Fabric.Cotton;
int fabNum = (int)fab;
string fabType = fab.ToString();
string fabVal = fab.ToString ("D");
double cost = GetPrice(fab);
Console.WriteLine("fabNum = {0}/nfabType = {1}/nfabVal = {2}/n", fabNum, fabType, fabVal);
Console.WriteLine("cost = {0}", cost);
}
7、Enum类的使用
Enum.IsDefinde、Enum.Parse两种方法经常一起使用，来确定一个值或符号是否是一个枚举的成员，然后创建一个实例。Enum.GetName打印出一个成员的值；Enum.GetNames打印出所有成员的值。其中注意typeof的使用。这一点很重要。
public enum MyFamily
{
YANGZHIPING = 1,
GUANGUIQIN = 2,
YANGHAORAN = 4,
LIWEI = 8,
GUANGUIZHI = 16,
LISIWEN = 32,
LISIHUA = 64,
}
string s = "YANGHAORAN";
if (Enum.IsDefined(typeof(MyFamily), s))
{
MyFamily f = (MyFamily)Enum.Parse(typeof(MyFamily), s);
GetMyFamily(f);
Console.WriteLine("The name is:" + Enum. GetName(typeof(MyFamily), 2));
string[] sa = Enum.GetNames(typeof(MyFamily));
foreach (string ss in sa)
{
Console.WriteLine(ss);
}
}
前些天在做类型发射的时候写道枚举反射，怎么也实例化不了一个枚举值，上网找了一下没发现！郁闷了老半天！于是去找原因结果我发现原来枚举类型发射实例化很简单：
Enum.Parse(type, value) 就可以了。
原来枚举是微软的基础类，我还把它当成是衍生类呢，真是糊涂呵呵！