try 
{
    int divisor = 0;
    if (divisor == 0) 
    {
        throw new Exception("Division by zero is not allowed");
    }
    int result = 10 / divisor;
} 
catch (Exception ex) 
{
    Console.WriteLine($"Error: {ex.Message}"); // 輸出: Error: Division by zero is not allowed
}

if (divisor == 0) 
{
    throw new InvalidOperationException("Divisor cannot be zero");
}

try 
{
    ProcessData();
} 
catch (Exception ex) 
{
    LogError(ex);
    throw; // 保留完整堆棧
    // throw ex; // 錯誤：會破壞調(diào)試信息
}

try 
{
    int.Parse("abc");
} 
catch (FormatException ex) when (ex.Message.Contains("input string")) 
{
    Console.WriteLine("Specific format error handled");
}

try 
{
    ValidateUser();
} 
catch (UnauthorizedAccessException ex) 
{
    ex.Data.Add("UserId", CurrentUserId);
    ex.Data.Add("Timestamp", DateTime.Now);
    throw;
}

async Task ProcessAsync() 
{
    try 
    {
        await SomeAsyncOperation();
    } 
    catch (AggregateException ae) 
    {
        foreach (var innerEx in ae.InnerExceptions) 
        {
            Console.WriteLine(innerEx.Message);
        }
    }
}

public class PaymentProcessingException : Exception 
{
    public decimal Amount { get; }
    public string TransactionId { get; }

    public PaymentProcessingException(decimal amount, string transactionId, string message) 
        : base(message) 
    {
        Amount = amount;
        TransactionId = transactionId;
    }
}

// 使用示例
throw new PaymentProcessingException(100m, "TX123", "Insufficient funds");

try 
{
    // 業(yè)務(wù)邏輯
} 
catch (Exception ex) 
{
    logger.LogError(ex, "Failed to process order {OrderId}", orderId);
    throw; // 重新拋出前記錄完整上下文
}

app.UseExceptionHandler(errorApp => 
{
    errorApp.Run(async context => 
    {
        context.Response.StatusCode = 500;
        var ex = context.Features.Get<IExceptionHandlerFeature>()?.Error;
        await context.Response.WriteAsync($"Error: {ex?.Message}");
    });
});

// 錯誤：用異?？刂普Ａ鞒?
try 
{
    int.TryParse("123", out int result);
} 
catch (FormatException) 
{
    result = 0; // 不推薦
}

if (!int.TryParse("123", out int result)) 
{
    result = 0;
}

throw new Exception($"Database connection failed: {connectionString}");

throw new Exception("Database connection failed. See logs for details.");
// 同時在日志中記錄完整信息（確保日志安全）
logger.LogError("Database connection failed for user {UserId}", userId);

try 
{
    // 外層操作
} 
catch (OuterException outerEx) 
{
    try 
    {
        // 補救操作
    } 
    catch (InnerException innerEx) 
    {
        throw new AggregateException("Outer operation failed", outerEx, innerEx);
    }
}

FileStream fs = null;
try 
{
    fs = new FileStream("file.txt", FileMode.Open);
    // 處理文件
} 
finally 
{
    fs?.Dispose();
}

// 更簡潔的C# 8.0+寫法
using var fs = new FileStream("file.txt", FileMode.Open);