Demonstrates a way to use TryParse to convert numbers

NumberConversionTests

using System;
using NUnit.Framework;

namespace NumberConversions
{
    [TestFixture]
    public class ConversionTests
    {
        private const string VALID_NUMBER = "12345";
        private const string INVALID_NUMBER = "BR549";
        private const int EXPECTED_NUMBER = 12345;

        [Test]
        public void TestConvertValidNumber()
        {
            var response = Convert.ToInt32(VALID_NUMBER);
            Assert.That(response, Is.EqualTo(EXPECTED_NUMBER));
        }

        [Test]
        [ExpectedException(typeof(FormatException))]
        public void TestConvertInvalidNumber()
        {
            Convert.ToInt32(INVALID_NUMBER);
        }

        [Test]
        public void TestTryParseValidNumber()
        {
            int num;
            var result = (Int32.TryParse(VALID_NUMBER, out num)) ? num : -1;
            Assert.That(result, Is.EqualTo(EXPECTED_NUMBER));
        }

        [Test]
        public void TestTryParseInvalidNumber()
        {
            int num;
            var result = (Int32.TryParse(INVALID_NUMBER, out num)) ? num : -1;
            Assert.That(result, Is.EqualTo(-1));
        }
    }
}