Using .Matches with regex for a char in fluent

Question

I have a class called Transaction which contains a property named source

Within the Transaction class I have some validation using FluentValidation, I am currently trying to validate the source property using regex however I'm having an issue

    //source isnt required but when present must be 1 character 'X' or 'Y'
    RuleFor(transaction => transacion.source)
        .Matches("^(X|Y)?$")
        .When(Transaction => transaction.source != null);

I am getting:

Error 1 FluentValidation.IRuleBuilderInitial<MyUtility.Transaction,char?> does not contain a definition for 'Matches' and the best extension method overload FluentValidation.DefaultValidatorExtensions.Matches<T>(FluentValidation.IRuleBuilder<T,string>, System.Text.RegularExpressions.Regex) has some invalid arguments

I have just used this exact same code for a different property with no problems, although that was a string not a char.

Answer 1

There's an extra dot . in your code between Matches and ("^(X|Y)?$").

.RuleFor(transaction => transaction.source)
    .Matches("^(X|Y)?$") // dot was here
    .When(transaction => transaction.source != null);

And as Robin pointed out, the regex is more readable in a [XY] format.

EDIT

I just reread your post and it says that the source property is a char so if you convert it to a string you won't get the error.

.RuleFor(transaction => transaction.source.HasValue ? transaction.source.ToString() : "")
    .Matches("^[XY]?$") // dot was here
    .When(transaction => transaction.source != null);