
using Xunit;
namespace ConsoleApp {
    public class ProgramTests {
        [Fact(DisplayName = "ParseStringToInt returns correct integer for valid input")] 
        public void ParseStringToInt_ReturnsCorrectInteger()
        {
            int result = Program.ParseStringToInt("42");
            Assert.Equal(42, result);
        }

        [Fact(DisplayName = "ParseStringToInt throws ArgumentNullException with specified message for null input")]
        public void ParseStringToInt_ThrowsArgumentNullExceptionForNull()
        {
            var ex = Assert.Throws<ArgumentNullException>(() => Program.ParseStringToInt(null));
            Assert.Equal("Input string is null.", ex.Message);
        }

        [Fact(DisplayName = "ParseStringToInt throws FormatException with specified message for invalid integer string")]
        public void ParseStringToInt_ThrowsFormatExceptionForInvalidFormat()
        {
            var ex = Assert.Throws<FormatException>(() => Program.ParseStringToInt("hello"));
            Assert.Equal("Input string is not in a correct format to parse to int.", ex.Message);
        }
    }
}

ProgramTests.cs

Master the art of robust C# programming by learning how to handle, create, and debug exceptions. This hands-on course guides you through real-world error handling scenarios, from basic try-catch to custom exceptions and safe file operations.

Learn the basics of exceptions in C#, how to use try-catch blocks, and why error handling is crucial for robust applications.

Learn to create your own exception types and use guard clauses to prevent invalid states in your code.

Master techniques for validating user input and safely parsing data to prevent runtime errors.

Handle file operations safely and learn to debug exceptions using stack traces and refactoring techniques.

Challenge: Specific Exception Catching

解答