如何将输入的用户值添加到 C# 中的表？ 返回最大值和最小值？

Question

using System;
using System.Data;

namespace ConsoleMinMax
{
    class MinMaxValue
    {
        static void Main(String[] args)
        {
            int[] tableWithValue = { 0, 0, 0, 0, 0 }; //This is a wrong way
            int i = 0;

            for (; i < 5; i++)
            {

                Console.WriteLine("Get number");
                int number = Convert.ToInt32(Console.ReadLine());
                tableWithValue[i] += number;

            }

            Console.WriteLine("Min value: " + tableWithValue.Min());
            Console.WriteLine("Max value: " + tableWithValue.Max());
        }

    }
}

I tried made a new table with user input to check max and min value. But I haven't idea how I can add user input value to table. I thought that value may add method tableWithValue.Append(number) like in Python but doesn't work in C#. Please for help.

Answer 1

In order to use Linq , in your case .Min() and .Max() you should add using System.Linq :

using System;
using System.Data;
using System.Linq; // <- you are going to query with a help of Linq (Min, Max etc.)

...

            // It should compile now
            Console.WriteLine($"Min value: {tableWithValue.Min()}");
            Console.WriteLine($"Max value: {tableWithValue.Max()}");
...

To brush your code slightly:

using System;
using System.Data;
using System.Linq;

namespace ConsoleMinMax
{
    class MinMaxValue
    {
        static void Main(String[] args)
        {
            // Array of 5 items
            int[] tableWithValue = new int[5];
            
            // do not use magic contsants - 5 - but tableWithValue.Length 
            for (int i = 0; i < tableWithValue.Length; i++)
            {
                Console.WriteLine("Get number");
                //TODO: Better int.TryParse to validate user input
                int number = Convert.ToInt32(Console.ReadLine());
                // why +=? Just assign =
                tableWithValue[i] = number;
            }

            // Time to simple Linq 
            Console.WriteLine($"Min value: {tableWithValue.Min()}");
            Console.WriteLine($"Max value: {tableWithValue.Max()}");
        }
    }
}

Answer 2

You are using array and array do not have "add" method (they can be concatenated with other array). For what you need to use list, like:

using System;
using System.Collections.Generic;
using System.Linq;

namespace ConsoleMinMax
{
    class MinMaxValue
    {
        static void Main(String[] args)
        {
            var tableWithValue = new List<int>();

            for (var i = 0; i < 5; i++)
            {
                Console.WriteLine("Get number");
                int number = Convert.ToInt32(Console.ReadLine());
                tableWithValue.Add(number);
            }

            Console.WriteLine("Min value: " + tableWithValue.Min());
            Console.WriteLine("Max value: " + tableWithValue.Max());
        }

    }
}

Answer 3

Gentlemen, please, use LINQ consistently and idiomatically:

var tableWithValue = Enumerable.Range(0, 5)
    .Select(i =>
    {
        Console.Write("Get number: ");
        return int.Parse(Console.ReadLine());
    })
    .ToList();

Console.WriteLine("Min value: " + tableWithValue.Min());
Console.WriteLine("Max value: " + tableWithValue.Max());