计算c#中大写字符数的最快方法

using System;
using System.Linq;

class Program
{
    static void Main()
    {
        string input = "Hello, World!";
        int uppercaseCount = input.Count(char.IsUpper);
        Console.WriteLine($"The number of uppercase characters in '{input}' is {uppercaseCount}.");
    }
}