关于使用委托进行解析，我在 C# 中做得对吗？

Question

I want to parse string into version numbers using delegate. The delegate requires a string as an argument and produces integer array as an output.

There are two errors

Error CS0136 A local or parameter named ' arrayString ' cannot be declared in this scope because that name is used in an enclosing local scope to define a local or parameter

Error CS0029 Cannot implicitly convert type ' System.Collections.Generic.List<int> ' to ' int '

namespace TEST
{
    class Program
    {
        public delegate int Parsing(string parsee);
       static void Main(string[] args)
        {

            Parsing parsee = new Parsing(Parse);
            Console.WriteLine(); 
        }

        public static int Parse(string arrayString)
        {
            Console.WriteLine("Write the version numbers : ");
            var input = Console.ReadLine();
             string[] arrayString = input.Split('-');
            List<int> listInt = new List<int>();
            foreach (string i in arrayString)
            {
                listInt.Add(Convert.ToInt32(i));
            }
            listInt.ToArray();
            foreach (var item in listInt)
            {
                Console.WriteLine(item);
            }

            return listInt;
        }
    }
}

I am a noob.

Answer 1

The identifier "arrayString" is defined twice.

Local variables as well as arguments are not allowed to be defined with the same name, otherwise accessing the identifier would have ambiguous meaning.

As long as the Parse method is named "parse", it should act as-is. It takes an argument as input and outputs the produced result, which is the only duty of it. while Console.ReadLine or Console.WriteLine are not a part of "Parse" but "Input".

You need more learning on the basic syntax and the built-in types before you start learning delegate.

The solution that maybe matches your requirement as a demo is:

namespace Test
{
    internal static class Program
    {
        internal static void Main(string[] args)
        {
            Console.WriteLine("Write the version numbers : ");
            var input = Console.ReadLine();

            var results = ParseInts(input.Split('-'), ParseInt);
            foreach (var item in results)
            {
                Console.WriteLine(item);
            }
        }

        private static IEnumerable<int> ParseInts(IEnumerable<string> values, Func<string, int> parser)
        {
            foreach (var item in values)
            {
                yield return parser(item);
            }
        }

        private static int ParseInt(string value)
        => Convert.ToInt32(value);
    }
}

But simply we use this to get int values:

var input = Console.ReadLine();
var results = input.Split('-').Select(int.Parse);

instead of writing everything.