Locked fields, tidy values & date windows

Three things a form needs once it survives its first submit. ReadOnlyWhen locks an answer that has been settled without hiding it from a keyboard or a screen reader. Trim() and Normalize(…) fix the value rather than complaining about it. A date or time Range(…) is enforced, not merely offered to the picker.

Live form

What the model holds

Tick confirmed and the reference and arrival lock — still readable, still copyable, still in the tab order. Type spaces around the email, or a lower-case reference, then leave the field.

{
  "Reference": "bk-1024",
  "ContactEmail": "",
  "Arrival": null,
  "CheckIn": null,
  "Confirmed": false
}

View source

var schema = BormBuilder.For<BookingRequest>()
    .Title("Booking")

    .Field(x => x.Reference, f => f
        // Fix the value, do not complain about it: on blur the reference is folded to upper case
        // and its stray spaces are dropped, so the model never stores " ab-12 ".
        .Normalize(v => v is string s ? s.Trim().ToUpperInvariant() : v)
        // Settled, not inapplicable. DisabledWhen would take this out of the tab order and stop a
        // screen reader announcing it at all — for a value the user still needs to read off.
        .ReadOnlyWhen(nameof(BookingRequest.Confirmed), BormConditionOperator.IsTrue))

    .Field(x => x.ContactEmail, f => f
        .AsEmail().Required()
        .Trim())                     // a rule that rejects " [email protected] " for its spaces helps nobody

    .Field(x => x.Arrival, f => f
        .As(BormFieldType.Date)
        // Rendered as the input's own min/max *and* enforced by the same rule, so a date typed past
        // the picker is reported rather than quietly accepted.
        .Range(DateTime.Today, DateTime.Today.AddMonths(6))
        .ReadOnlyWhen(nameof(BookingRequest.Confirmed), BormConditionOperator.IsTrue))

    .Field(x => x.CheckIn, f => f
        .As(BormFieldType.Time)
        .Range(new TimeOnly(14, 0), new TimeOnly(22, 0)))

    .Field(x => x.Confirmed, f => f.AsSwitch())
    .Build();

// A "Saved." banner belongs to the save, not to the absence of errors.
if (state.IsSubmitSuccessful) { /* … */ }

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