#### [Abblix\.SecurityEvents](https://www.abblix.com/en/docs/api/abblix-securityevents 'index')
### [Abblix\.SecurityEvents\.Subjects](https://www.abblix.com/en/docs/api/abblix-securityevents/Abblix.SecurityEvents.Subjects 'Abblix\.SecurityEvents\.Subjects')

## PhoneNumberSubject Class

Identifies a subject by a telephone number \(RFC 9493 Section 3\.2\.5\)\.

```csharp
public sealed class PhoneNumberSubject : Abblix.SecurityEvents.Subjects.SubjectIdentifier
```

Inheritance [System\.Object](https://learn.microsoft.com/en-us/dotnet/api/system.object 'System\.Object') → [SubjectIdentifier](https://www.abblix.com/en/docs/api/abblix-securityevents/Abblix.SecurityEvents.Subjects.SubjectIdentifier 'Abblix\.SecurityEvents\.Subjects\.SubjectIdentifier') → PhoneNumberSubject
### Constructors

## PhoneNumberSubject\(string\) Constructor {#Abblix.SecurityEvents.Subjects.PhoneNumberSubject.PhoneNumberSubject(string)}

Identifies a subject by a telephone number \(RFC 9493 Section 3\.2\.5\)\.

```csharp
public PhoneNumberSubject(string phoneNumber);
```
#### Parameters

###### `phoneNumber` [System\.String](https://learn.microsoft.com/en-us/dotnet/api/system.string 'System\.String') {#Abblix.SecurityEvents.Subjects.PhoneNumberSubject.PhoneNumberSubject(string).phoneNumber}

The subject's full telephone number including its international dialling prefix, formatted
according to E\.164\. REQUIRED, and must be neither null nor empty\.
### Properties

## PhoneNumberSubject\.PhoneNumber Property {#Abblix.SecurityEvents.Subjects.PhoneNumberSubject.PhoneNumber}

The telephone number, as received\.

```csharp
public string PhoneNumber { get; }
```

#### Property Value
[System\.String](https://learn.microsoft.com/en-us/dotnet/api/system.string 'System\.String')

### Remarks
E\.164 form is what RFC 9493 Section 3\.2\.5 requires of the sender, so this library neither
reformats an incoming value nor rejects one that departs from E\.164: a receiver that
discarded such an event would lose a signal it could still act on, and a receiver that
rewrote it would be guessing at the sender's intent\. Compare through
[PhoneNumberCanonicalization](https://www.abblix.com/en/docs/api/abblix-securityevents/Abblix.SecurityEvents.Subjects.PhoneNumberCanonicalization 'Abblix\.SecurityEvents\.Subjects\.PhoneNumberCanonicalization') when values from different senders must meet\.