C#：统计字符串中每个字符的个数

具体代码如下：

namespace demo
{
    public class Program
    {
        static void Main(string[] args)
        {
            string str = "hi,good morning.";
            Console.WriteLine($"字符串：{str}");
            Dictionary<char, int> dic = Count(str);
            foreach(var c in dic)            
                Console.WriteLine($" '{c.Key}'：{c.Value}");            
            Console.ReadKey();
        }
        static Dictionary<char,int> Count(string str)
        {
            Dictionary<char, int> dic = new Dictionary<char, int>();
            char[] chars = str.ToArray();
            foreach(char c in chars)
            {
                if (dic.ContainsKey(c))
                    dic[c]++;
                else
                    dic.Add(c, 1);
            }
            return dic;
        }
    }
}

执行结果：