Enum 轉成string & int

using System;

public class CSharpLab

{

public enum State

{

Init, Open, Proc, Close, Done = 9

}

public static void Test()

{

State st = State.Init;

//列出所有名稱

foreach (string en in Enum.GetNames(typeof(State)))

Console.WriteLine("Enum Name: " + en);

//列舉背後有值, 預設由零開始排, 但也可自訂

//TIPS: typeof(State)與st.GetType()都可取得列舉型別

foreach (int v in Enum.GetValues(st.GetType()))

Console.WriteLine("Enum Value: " + v.ToString());

//將列舉轉為字串

Console.WriteLine("Enum To String: " + st.ToString());

//將字串轉為列舉

st = (State)Enum.Parse(typeof(State), "proc", true);

Console.WriteLine("String To Enum: " + st);

try {

Console.WriteLine("String To Enum(not found): " + 

Enum.Parse(typeof(State), "WTF"));

} catch (Exception ex) {

Console.WriteLine("Error when Enum.Parse: " + ex.Message);

}

//將列舉轉為數字

Console.WriteLine("Enum to Int: " + st + " " + (int)st);

//將數字轉回列舉

st = (State)9;

Console.WriteLine("Int to Enum: " + st);

//小心數字轉換對不上時不會有錯誤，但會出現非列舉值

st = (State)100;

Console.WriteLine("Int(100) to Enum: " + st);

//如果數字有連續，可以用+1, -1找上一個下一個

//注意: 以下範例並未檢查邊界及數值不連續的狀況, 

//並非嚴謹寫法，僅為簡單示意，勿用於正式用途

st = State.Proc;

State next = (State)((int)st)+1;

State prev = (State)((int)st)-1;

Console.WriteLine("Now = " + st + " Next = " + next + " Prev = " + prev);

}

}