如下所示：

复制代码 代码如下:

using System;

using System.Collections.Generic;

using System.Text;

namespace ConsoleApplication1

{

class Class1

{

static string[] str = { "A", "B", "C", "D", "E" };

static void Main()

{

Dictionary<string, int> dic = new Dictionary<string, int>();

//将数组元素添加到dic

for (int i = 0; i < str.Length; i++)

{

dic.Add(str[i], i);

}

GetDic(dic);

Console.ReadLine();

}

static void GetDic(Dictionary<string, int> dd)

{

Dictionary<string, int> dic = new Dictionary<string, int>();

//主要是抓住AB,AC,AD,AE,然后就是开始从 BC，BD这样的原理用dd中的键与数组的中对应索引比dd中的value大进行组合

foreach (KeyValuePair<string, int> kk in dd)

{

for (int i = kk.Value + 1; i < str.Length; i++)

{

Console.WriteLine(kk.Key + str[i]);

dic.Add(kk.Key + str[i], i);

}

}

//递归

if (dic.Count > 0) GetDic(dic);

}

}

}

结果

AB

AC

AD

AE

BC

BD

BE

CD

CE

DE

ABC

ABD

ABE

ACD

ACE

ADE

BCD

BCE

BDE

CDE

ABCD

ABCE

ABDE

ACDE

BCDE

ABCDE