我应该为我的实体框架查询捕获哪些错误？

Question

我有一个ASP.NET Core MVC应用程序（在.NET 6上运行），其中有一些客户的数据库。

应用程序的目的只是让用户输入一堆限制，这些约束将过滤数据库中的客户，并返回过滤后的客户列表，然后将其显示给用户。

我有一个控制器操作，它接受了约束查询，看起来像这样：

[HttpPost]
public async Task<IActionResult> Query(QueryModel query)
{
    var customers = await _context.Customers.AsQueryable().FilterCustomerList(query);

    ViewBag.Name = query.Name;
    ViewBag.Age = query.Age;
    ViewBag.SalesPersonName = query.salespersonName;

    return View("Index", customers);
}

然后，此功能正在过滤客户：

public static async Task<List<CustomerModel>> FilterCustomerList(this IQueryable<CustomerModel> customersQuery, QueryModel query)
{
    customersQuery = customersQuery
    .Include(x => x.Adress)
    .Include(x => x.purchases).ThenInclude(x => x.Car)
    .Include(x => x.purchases).ThenInclude(x => x.SalesPerson.Adress)
    .Where(query.Name != default, x => x.Name.Equals(query.Name))
    .Where(query.Surname != default, x => x.Surname.Equals(query.Surname))
    .Where(query.Age != default, x => x.Age.Equals(query.Age))
    .Where(query.Country != default, x => x.Adress.Country.Equals(query.Country))
    .Where(query.Town != default, x => x.Adress.Town.Equals(query.Town))
    .Where(query.ZipCode != default, x => x.Adress.ZipCode.Equals(query.ZipCode))
    .Where(query.Street != default, x => x.Adress.street.Equals(query.Street))
    .Where(query.HouseNr != default, x => x.Adress.HouseNumber.Equals(query.HouseNr))
    .Where(query.To != query.From, x => x.Created > query.From && x.Created < query.To)
    .Where(query.purchaseDateFrom != query.purchaseDateTo, x => x.purchases.Any(
        x => x.OrderDate > query.purchaseDateFrom && x.OrderDate < query.purchaseDateTo))
    .Where(query.model != default, x => x.purchases.Any(p => p.Car.Model.Equals(query.model)))
    .Where(query.make != default, x => x.purchases.Any(p => p.Car.Make.Equals(query.make)))
    .Where(query.color != default, x => x.purchases.Any(p => p.Car.CarColor == query.color))
    .Where(query.paidPrice != default, x => x.purchases.Any(p => p.PricePaid.Equals(query.recPrice)))
    .Where(query.recPrice != default,
        x => x.purchases.Any(p => p.Car.RecommendedPrice.Equals(query.recPrice)))
    .Where(query.recPriceLow != default && query.recPriceTop != default, x
        => x.purchases.Any(p =>
            p.Car.RecommendedPrice > query.recPriceLow && p.Car.RecommendedPrice < query.recPriceTop))
    .Where(query.paidPriceTop != default && query.paidPriceLow != default, x
        => x.purchases.Any(p => p.PricePaid > query.paidPriceLow && p.PricePaid < query.paidPriceTop))
    .Where(query.salespersonName != default,
        c => c.purchases.Any(p => p.SalesPerson.Name.Equals(query.salespersonName)))
    .Where(query.salespersonJobTitle != default,
        c => c.purchases.Any(x => x.SalesPerson.JobTitle == query.salespersonJobTitle))
    .Where(query.salesPersonSalary != default, c => c.purchases.Any(x => query.salesPersonSalary.Equals(x
        .SalesPerson.Salary)))
    .Where(query.salesPersonSalaryFrom != default && query.salesPersonSalaryFrom != default, c =>
        c.purchases.Any(x => x.SalesPerson.Salary < query.salesPersonSalaryFrom &&
                             x.SalesPerson.Salary > query.salesPersonSalaryTo))
    .Where(query.SalesPersonCountry != default,
        c => c.purchases.Any(x => x.SalesPerson.Adress.Country.Equals(query.SalesPersonCountry)))
    .Where(query.SalesPersonTown != default,
        c => c.purchases.Any(x => x.SalesPerson.Adress.Town.Equals(query.SalesPersonTown)))
    .Where(query.SalesPersonZipCode != default, c => c.purchases.Any(x =>
        x.SalesPerson.Adress.ZipCode.Equals(query.ZipCode)))
    .Where(query.SalesPersonStreet != default, c => c.purchases.Any(x =>
        x.SalesPerson.Adress.street.Equals(query.SalesPersonStreet)))
    .Where(query.salesPersonHouseNr != default, c => c.purchases.Any(x =>
        x.SalesPerson.Adress.HouseNumber.Equals(query.salesPersonHouseNr)));

switch (query.sortBy)
{
    case SortBy.Age_desc:
    {
        customersQuery = customersQuery.OrderByDescending(c => c.Age);
        break;
    }
    case SortBy.CreationDate_desc:
    {
        customersQuery = customersQuery.OrderByDescending(c => c.Created);
        break;
    }
    case SortBy.Age_asc:
    {
        customersQuery = customersQuery.OrderBy(c => c.Age);
        break;
    }
    case SortBy.CreationDate_asc:
    {
        customersQuery = customersQuery.OrderBy(c => c.Created);
        break;
    }
}

var customers = await customersQuery
    .ToListAsync();

return customers;
}

这只是条款中的一个很长的块。

现在，我认为我应该有一些问题，这些东西可能会发现这些查找过程中发出的任何错误。

我真的无法弄清楚当我只做查找时，我可能会期望哪种例外，也无法弄清楚如何挑衅，所以我可以找出答案。

另外，我希望能够与控制器通信发生了错误，并且应该显示明智的错误。

最佳/最正常的练习是要投掷错误并显示一些标准错误页面，还是可以让控制器操作处理错误？

Answer 1

现在，我认为我应该有一些可以抓住的东西
这些查找期间发出的任何错误。

如果您不确定在哪种情况下得到哪些例外，请使用调试器和一些测试代码来找出您实际上可能期望的例外：

// TODO: create one of your error conditions
try
{
   _context.SaveChanges();
}
catch (Exception e)
{
    Console.WriteLine(e.GetType()); // what is the real exception?
}

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