C#: معالجة الاستثناءات

try
{
    int result = 10 / 0;
}
catch (DivideByZeroException ex)
{
    Console.WriteLine($"Caught exception: {ex.Message}");
}
finally
{
    Console.WriteLine("finally block always executes");
}

Caught exception: Attempted to divide by zero.
finally block always executes

try
{
    int[] arr = { 1, 2, 3 };
    Console.WriteLine(arr[10]);
}
catch (IndexOutOfRangeException ex)
{
    Console.WriteLine($"Index out of bounds: {ex.Message}");
}
catch (Exception ex)
{
    Console.WriteLine($"General exception: {ex.Message}");
}

Index out of bounds: Index was outside the bounds of the array.

try
{
    int num = int.Parse("hello");
}
catch (FormatException)
{
    Console.WriteLine("Format exception: string cannot be converted to integer");
}

string s = null;
try
{
    Console.WriteLine(s.Length);
}
catch (NullReferenceException)
{
    Console.WriteLine("Null reference exception: object is null");
}

Format exception: string cannot be converted to integer
Null reference exception: object is null

Object
  └─ Exception
       └─ SystemException
            ├─ FormatException
            ├─ NullReferenceException
            ├─ IndexOutOfRangeException
            ├─ DivideByZeroException
            ├─ OverflowException
            ├─ FileNotFoundException
            └─ ArgumentException
                 └─ ArgumentNullException

try
{
    int zero = 0;
    int result = 100 / zero;
}
catch (Exception ex)
{
    Console.WriteLine($"Message: {ex.Message}");
    Console.WriteLine($"Source: {ex.Source}");
    Console.WriteLine($"TargetSite: {ex.TargetSite}");
}

Message: Attempted to divide by zero.
Source: ConsoleApp
TargetSite: Void Main()

void CheckAge(int age)
{
    if (age < 0)
    {
        throw new ArgumentException("Age cannot be negative", nameof(age));
    }
    Console.WriteLine($"Age: {age}");
}

try
{
    CheckAge(-5);
}
catch (ArgumentException ex)
{
    Console.WriteLine(ex.Message);
}

Age cannot be negative (Parameter 'age')

void InnerMethod()
{
    throw new InvalidOperationException("Internal error");
}

void OuterMethod()
{
    try
    {
        InnerMethod();
    }
    catch (Exception ex)
    {
        throw;
    }
}

try
{
    OuterMethod();
}
catch (Exception ex)
{
    Console.WriteLine(ex.StackTrace);
}

   at InnerMethod() in Program.cs:line 2
   at OuterMethod() in Program.cs:line 10

try
{
    throw new HttpRequestException("Network timeout, please retry later");
}
catch (HttpRequestException ex) when (ex.Message.Contains("timeout"))
{
    Console.WriteLine("Caught timeout exception, preparing to retry");
}
catch (HttpRequestException ex)
{
    Console.WriteLine($"Other network exception: {ex.Message}");
}

Caught timeout exception, preparing to retry

class InsufficientBalanceException : Exception
{
    public decimal Balance { get; }
    public decimal Amount { get; }

    public InsufficientBalanceException()
        : base("Insufficient balance") { }

    public InsufficientBalanceException(string message)
        : base(message) { }

    public InsufficientBalanceException(string message, Exception innerException)
        : base(message, innerException) { }

    public InsufficientBalanceException(decimal balance, decimal amount)
        : base($"Insufficient balance: current balance {balance}, required {amount}")
    {
        Balance = balance;
        Amount = amount;
    }
}

class BankAccount
{
    public decimal Balance { get; private set; }

    public BankAccount(decimal balance)
    {
        Balance = balance;
    }

    public void Withdraw(decimal amount)
    {
        if (amount > Balance)
        {
            throw new InsufficientBalanceException(Balance, amount);
        }
        Balance -= amount;
        Console.WriteLine($"Withdrawal successful, balance: {Balance}");
    }
}

var account = new BankAccount(100);
try
{
    account.Withdraw(200);
}
catch (InsufficientBalanceException ex)
{
    Console.WriteLine(ex.Message);
    Console.WriteLine($"Balance: {ex.Balance}, attempted withdrawal: {ex.Amount}");
}

Insufficient balance: current balance 100, required 200
Balance: 100, attempted withdrawal: 200

try
{
    int value = int.Parse(input);
    Console.WriteLine(100 / value);
}
catch (FormatException)
{
    Console.WriteLine("Input is not a valid integer");
}
catch (DivideByZeroException)
{
    Console.WriteLine("Cannot input zero");
}

try
{
    File.WriteAllText("data.txt", content);
}
catch (Exception)
{
}

FileStream fs = null;
try
{
    fs = new FileStream("data.txt", FileMode.Open);
    int b = fs.ReadByte();
}
finally
{
    fs?.Dispose();
}

using (var fs = new FileStream("data.txt", FileMode.Open))
{
    int b = fs.ReadByte();
}

try
{
    SaveToFile();
}
catch (IOException ioEx)
{
    throw new ApplicationException("Failed to save data", ioEx);
}