String array to Int array

try this

string str = "1 1 3 1 2 2 0 0";
int[] array = str.Split(' ').Select(int.Parse).ToArray(); 

Demo

You need to use String.Split Method to split your string with space' ' in an array of strings and then convert each element to integer. You can iterate string array using System.Linq in efficient manner

using System.Linq; //You need add reference to namespace

static void Main()
{
    string numbersStr = "1 1 3 1 2 2 0 0";
    int[] numbersArrary = numbersStr.Split(' ').Select(n => Convert.ToInt32(n)).ToArray();
}

DEMO

You are not splitting the string using space delimiter.

        string first = Console.ReadLine();
        int len = first.Split(new []
                         {' '},StringSplitOptions.RemoveEmptyEntries).Length;
        string[] First = new string[len];

        for (int i = 0; i < len; i++)
        {
            First[i] = first.Split(' ')[i];
        }

        int[] Arr = new int[First.Length];//int array for string console values
        for (int i = 0; i < First.Length; i++)//goes true all elements and converts them into Int32
        {
            Arr[i] = Convert.ToInt32(First[i].ToString());
        }
        for (int i = 0; i < Arr.Length; i++)//print array to see what happened
        {
            Console.WriteLine(Arr[i]);
        }

Try changing it to this:

string s = Console.ReadLine();
string[] arr = s.Split(' '); //Split the single string into multiple strings using space as delimiter
int[] intarr = new int[arr.Length];

for(int i=0;i<arr.Length;i++)
 {
  intarr[i] = int.Parse(arr[i]); //Parse the string as integers and fill the integer array
 }

for(int i=0;i<arr.Length;i++)
 {
  Console.Write(intarr[i]);
 }

You cant try with "1 1 3 1 2 2 0 0", because it is trying to parse the spaces between the numbers. If you want your program to work you have to either make your input string like that: "11312200" or you can make a char array or just a single char if you dont have more than one separator where you assign and then .split the string by passing the separator, like that:

string Numbers = "1 1 3 1";

string[] seperatedNumbers = Numbers.Split(' ');

// perform your following actions

You can do this with a simple extension method:

Using:

 var stringArray = "0,1,2,3,4,5";
 stringArray.ParseIntArray();

Code:

//separator parameter: default value is ',' you can use whatever you want. ' ', '|', ';'

public static int[] ParseIntArray(this string source, char separator = ',')
{
   return Array.ConvertAll(source.Split(separator), int.Parse);
}

If you don't want to get an exception you can use this. It returns new int[] {0} when throw an exception.

Using:

var stringArray = "0,1,2,3,4,5";
stringArray.TryParseIntArray();

Code:

public static int[] TryParseIntArray(this string source, char separator = ',')
{
   int[] arrInt;

   try
     {
       arrInt = Array.ConvertAll(source.Split(separator), int.Parse);          
     }
   catch (Exception ex)
     {
       arrInt = new int[] { 0 };
     }

  return arrInt;
}