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C# C# Objects Loops and Final Touches Foreach Loops

Posted by Fabiola Barrientos
Fabiola Barrientos
9,467 Points

Error, operator += not valid

Whenever i try to use the operator "+=", it tells me it isnt valid to use in int or double units. Last time i tried to get the average of something I used "+=", and i have no idea how to do it otherwise.

FrogStats.cs 
namespace Treehouse.CodeChallenges
{
    class FrogStats
    {
        public static double GetAverageTongueLength(Frog[] frogs)
        {
            int sum = 0;
            foreach( Frog TongueLength in frogs )
            {
                sum += TongueLength;
            }
            return sum / frogs.Length;
        }
    }
}
Frog.cs 
namespace Treehouse.CodeChallenges
{
    public class Frog
    {
        public int TongueLength { get; }

        public Frog(int tongueLength)
        {
            TongueLength = tongueLength;
        }
    }
}

1 Answer

Tim Danner
Tim Danner
3,284 Points
Tim Danner
Tim Danner
3,284 Points

The problem here is that you're trying to assign frog objects to an int variable, which causes type error.

Keep in mind that when you're looping through an array of a certain type, all the elements will also be of that type. To access the properties or methods, use the dot notation:

namespace Treehouse.CodeChallenges
{
    class FrogStats
    {
        public static double GetAverageTongueLength(Frog[] frogs)
        {
            int sum = 0;
            foreach (Frog frog in frogs)
            {
                // access the TongueLength property through dot notation
                sum += frog.TongueLength;
            }
            return sum / frogs.Length;
        }
    }
}