C#•2y ago

❔ (MVC web app) How can I handle exceptions/errors in this case?

So I was thinking of placing all this code (the one inside the function) inside a try catch block, and in the catch statement, if there's an exception catch it and then display an error message such as "Something went wrong, error #0001", is it bad practice? what could i do instead?

public IActionResult AddTransaction(Models.Transaction transaction, CategoryViewModel cvm)
{
    var userId = transaction.UserId;
    var findUserTask = _userManager.FindByIdAsync(userId);

    Task.WaitAll(findUserTask);

    var user = findUserTask.Result;

    if (user == null)
    {
        return RedirectToPage("/Account/Login", new { area = "Identity" });
    }

    decimal transactionValue = transaction.Value;

    transactionValue = decimal.Parse(transactionValue.ToString());

    var categories = _categoryService.GetAllCategories();
    var transactions = _transactionService.GetAllTransactions();

    var transactionCategory = categories.Where(c => c.Id == transaction.CategoryId).First();

    //transactionCategory.TotalValue += transaction.Value;

    var selectedCurrencyOption = JsonSerializer.Deserialize<Currency>(cvm.CurrencyObjectJson);

    transaction.CurrencyCode = selectedCurrencyOption.CurrencyCode;
    transaction.CurrencyNativeSymbol = selectedCurrencyOption.NativeSymbol;

    _transactionService.AddTransaction(transaction);
    _context.SaveChanges();

    ChangeUserCategoryValue(user, transactionCategory.Name, transactionValue).Wait();

    user = findUserTask.Result;

    Currency currencyObject = new Currency
    {
        CurrencyCode = user.CurrencyCode,
        NativeSymbol = user.CurrencyNativeSymbol,
        Name = string.Empty
    };

    string currencyJson = JsonSerializer.Serialize(currencyObject);
    UpdateCurrency(currencyJson);

    return Redirect("https://localhost:7229");
}

public IActionResult AddTransaction(Models.Transaction transaction, CategoryViewModel cvm)
{
    var userId = transaction.UserId;
    var findUserTask = _userManager.FindByIdAsync(userId);

    Task.WaitAll(findUserTask);

    var user = findUserTask.Result;

    if (user == null)
    {
        return RedirectToPage("/Account/Login", new { area = "Identity" });
    }

    decimal transactionValue = transaction.Value;

    transactionValue = decimal.Parse(transactionValue.ToString());

    var categories = _categoryService.GetAllCategories();
    var transactions = _transactionService.GetAllTransactions();

    var transactionCategory = categories.Where(c => c.Id == transaction.CategoryId).First();

    //transactionCategory.TotalValue += transaction.Value;

    var selectedCurrencyOption = JsonSerializer.Deserialize<Currency>(cvm.CurrencyObjectJson);

    transaction.CurrencyCode = selectedCurrencyOption.CurrencyCode;
    transaction.CurrencyNativeSymbol = selectedCurrencyOption.NativeSymbol;

    _transactionService.AddTransaction(transaction);
    _context.SaveChanges();

    ChangeUserCategoryValue(user, transactionCategory.Name, transactionValue).Wait();

    user = findUserTask.Result;

    Currency currencyObject = new Currency
    {
        CurrencyCode = user.CurrencyCode,
        NativeSymbol = user.CurrencyNativeSymbol,
        Name = string.Empty
    };

    string currencyJson = JsonSerializer.Serialize(currencyObject);
    UpdateCurrency(currencyJson);

    return Redirect("https://localhost:7229");
}

18 Replies

Angius•2y ago

Ooof ouch owie that .Result Use proper async code pls For exceptions, you'd usually rely on the exception handling middleware

softmek•2y ago

In the provided AddTransaction method, it seems there's a need for improvements related to asynchronous operations, exception handling, and code structure. Here's an enhanced version with comments to illustrate some changes:

softmek•2y ago

Optimize.cs

XDOP•2y ago

sorry thank you for your answer, so it is okay to use a try catch block for all the code?

softmek•2y ago

💯 . I have over 7 year experience and that's the best way you will ever handle that, but avoid absolute url inside your application https://www.linkedin.com/in/haron-njuguna/

XDOP•2y ago

yeah, will fix it, thank you so much!

softmek•2y ago

If you get stuck, You can always reach out in my DM. especially ln

XDOP•2y ago

btw i was thinking of redirecting to the same view but changing the red <p> as i showed here if there was an error, do you think it is better than redirecting to an error view? @softmek

softmek•2y ago

You can use alert message for that. Imagine all cards didn’t load, the page will be well written in red haha! 😛 Which FE framework are you using, i can suggest what I use

XDOP•2y ago

i'm not proficient in any framework yet so i'm just using html with razor

XDOP•2y ago

https://github.com/JsPeanut/MVC.Budget/blob/main/MVC.Budget/MVC.Budget.JsPeanut/Views/Categories/Index.cshtml

GitHub

MVC.Budget/MVC.Budget/MVC.Budget.JsPeanut/Views/Categories/Index.cs...

Contribute to JsPeanut/MVC.Budget development by creating an account on GitHub.

softmek•2y ago

You can use https://codeseven.github.io/toastr/demo.html

XDOP•2y ago

that is amazing it should be shown after reloading the page right?

softmek•2y ago