如何在C＃中生成所有可能的3个字符的字符串？

Question

The question is :

How to generate a list of all possible 3-chars strings in C#?

To clairify, that's within the domain of 64 ₁₀ and 90 ₁₀

Answer 1

IEnumerable<string> GetAllStrings(params char[] inputCharacterSet) {
    return from n in inputCharacterSet
           from m in inputCharacterSet
           from k in inputCharacterSet
           select new string(new [] { n, m, k });
}

Answer 2

public IEnumerable<String> Get3CharStrings(char[] domain)
{
    foreach(char a in domain)
     foreach(char b in domain)
      foreach(char c in domain)
       yield return "" + a + b + c;
}

This is actually quite a bit slower than the LINQ solution posted by Mehrdad, although most of the difference lies in the use of return "" + a + b + c instead of return new string(new[] { a, b, c}) .

Actual statistics (26-character alphabet, 10k iterations:

Mehrdad's code: 72.983 seconds
My code: 127.205 seconds
My code with Mehrdad's return statement: 75.055 seconds