
using Xunit;
using System;
using System.IO;

namespace ConsoleApp {
    public class ProgramTests {
        [Fact(DisplayName = "Returns 'File does not exist.' if file is missing")]
        public void ReadFileContent_ReturnsMessageIfFileMissing()
        {
            string testFile = "nonexistent_testfile.txt";
            if (File.Exists(testFile)) File.Delete(testFile);
            string result = Program.ReadFileContent(testFile);
            Assert.Equal("File does not exist.", result);
        }

        [Fact(DisplayName = "Returns file content if file exists")]
        public void ReadFileContent_ReturnsContentIfFileExists()
        {
            string testFile = "temp_testfile.txt";
            string expected = "Hello, file!";
            File.WriteAllText(testFile, expected);
            try
            {
                string result = Program.ReadFileContent(testFile);
                Assert.Equal(expected, result);
            }
            finally
            {
                if (File.Exists(testFile)) File.Delete(testFile);
            }
        }
    }
}

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: Debugging a Broken Program

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