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C# C# Basics (Retired) Perfect if / else if / else

Niyazi Piriyev
Niyazi Piriyev
970 Points
Posted by Niyazi Piriyev
Niyazi Piriyev
970 Points

System.ArgumentNullException: 'Value cannot be null. error for int.Parse(int input)

I am getting error when i try tu run this code on Visual studio.

CodeChallenge.cs 
string input = Console.ReadLine();
int temperature = int.Parse(input);

if (temperature <21)
{
    Console.WriteLine("Too cold!");
}
else {Console.WriteLine("too hot!");}

1 Answer

Matti Mänty
Matti Mänty
5,885 Points
Matti Mänty
Matti Mänty
5,885 Points

I'm not 100% sure here, but I think either your input is empty, or you are using the wrong parse method. Try using Int32.Parse(string).

string input = Console.ReadLine();
int temperature = Int32.Parse(input);

Or use TryParse to handle possible errors.

string input = Console.ReadLine();
int temperature;
if(Int32.TryParse(input, out temperature))
{
   if (temperature <21)
   {
      Console.WriteLine("Too cold!");
   }
   else {Console.WriteLine("too hot!");}
}