```
public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private void txtTestPrime_Click(object sender, EventArgs e)
        {
            TestPrime myNumber = new TestPrime();
            lblAnswer.Text = 
                myNumber.TestPrime(ToInt16(txtTestPrime.Text)) ? "it is prime!" : "it is NOT prime!";
        }

    }
    public class TestPrime(int number)
    {
        bool prime;

    }

```

it doesnt like this line:

```
public class TestPrime(int number)

```

i am getting this error: invalid token '(' in class, struct, or interface member declaration

also getting `expect { and ;` on that line 

also on this line:

```
myNumber.TestPrime(ToInt16(txtTestPrime.Text)) ? "it is prime!" : "it is NOT prime!"; 

```

im getting Error 4 'WindowsFormsApplication1.TestPrime' does not contain a definition for 'TestPrime' and no extension method 'TestPrime' accepting a first argument of type 'WindowsFormsApplication1.TestPrime' could be found (are you missing a using directive or an assembly reference?)

perhaps it is one main thing that i am doing wrong. please help!