Fluent validation add rule with index

Question

I make a fluent validation class for this model

 public class OnlineCashierRequest
 {
    Guid InvoiceId { get; set; }      
    string ClientPhoneOrEmail { get; set; }    
    List<IOnlineCashierProduct> Products { get; set; }
 }

public interface IOnlineCashierProduct
{
     string Name { get; set; }
     decimal Amount { get; set; }
     int Count { get; set; }
}

I have a rule for products where Amount equals null. But how can I write in message row index like $"Amount is less zero for row {rowIndex}"

RuleForEach(t => t.Products)
    .Must(x => x.Amount < 0)
    .WithMessage(x => $"[{rowIndex}] Amount must be greater then zero\r\n");

Check this https://stackoverflow.com/questions/27213058/how-can-i-access-the-collection-item-being-validated-when-using-ruleforeach — mtkachenko, Jun 11 '19 at 08:01
Would it not be better to use the `Name` of the `IOnlineCashierProduct` in the log message? — Chris, Jun 11 '19 at 08:48
@chris No, there is also may be an error with empty productName — user2455111, Jun 11 '19 at 09:02

score 1 · Answer 1 · answered Feb 18 '22 at 17:32

1

https://docs.fluentvalidation.net/en/latest/collections.html

RuleForEach(t => t.Products)
    .Must(x => x.Amount < 0)
    .WithMessage(x => $"[{CollectionIndex}] Amount must be greater than zero\r\n");

answered Feb 18 '22 at 17:32

Simon H

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Wouldn't it need to be `$"[{{CollectionIndex}}] Amount must be greater than zero\r\n"` because of the string interpolation? – Elias May 17 '23 at 09:53

Fluent validation add rule with index

1 Answers1