C＃計算數字和字母

Question

我想計算在我正在檢查的行中使用了多少數字（ 僅0、1、2、3 ）和字母（ a，b，c，d ）-它們是混合的，例如： 3b1c1c1a1a1a0b1a1d3d0a3c 。 我怎么算呢？

Answer 1

int numbers = 0;
int letters = 0;

foreach(char a in myString)
{
  if (Char.IsDigit(a))
    numbers ++;
  else if (Char.IsLetter(a)){
    letters ++;
}

Answer 2

如果需要重新使用預定義的Linq表達式，也可以使用它們：

var characterList = "234234abce".ToCharArray();
var validCharacters = "0123abcd".ToCharArray();

Func<char, bool> ValidLetter = delegate(char c){
    return Char.IsLetter(c) && validCharacters.Contains(c);
};
Func<char, bool> ValidNumber = delegate(char c){
    return Char.IsDigit(c) && validCharacters.Contains(c);
};

var letterCount = characterList.Where(c => ValidLetter(c)).Count();
var numberCount = characterList.Where(c => ValidNumber(c)).Count();

Answer 3

有一種方法可以做到這一點：

int count = myString.ToCharArray().Where(c => Char.IsLetterOrDigit(c)).Count();

如果要拆分它們，則：

int letterCount = myString.ToCharArray().Where(c => Char.IsLetter(c)).Count();
int numberCount = myString.ToCharArray().Where(c => Char.IsDigit(c)).Count();

如果要根據數字過濾它們：

 List<char> searchFor = new List<char>() { '0', '1', '2', '3' };
 int numberCount = myString.ToCharArray().Where(c => searchFor.Contains(c)).Count();

Answer 4

您可以使用ASCII代碼使其正常工作

             for(int i = 0 ; i < str.Length ; i++){
             int asciicode = (int)str[i];
             if(asciicode >= 48 && asciicode <= 57)
                        number++;
             else
                      alphabet++;                 
      } 

Answer 5

這是查找字符“ 1”的計數的示例：

        string input = "3b1c1c1a1a0b1a1d3d0a3c";
        int count = input.ToArray().Count(i => i == '1');

Answer 6

以下滿足您的要求：

string acceptedChars = "0123abcd";

var res = "3b1c1c1a1a0b1a1d3d0a3c".ToCharArray()
    .Where(x => acceptedChars.Contains(x))
    .GroupBy(x => char.IsDigit(x))
    .Select(g => new{ isDigit = g.Key, count = g.Count() } );

var digitsCount = res.Single(r => r.isDigit == true).count;
var lettersCount = res.Single(r => r.isDigit == false).count;