'Declaration
 
<JetBrains.Annotations.NotNullAttribute()>
Public Property ClientId As String

'Usage
 
Dim instance As SparkplugConnectionStateChangedEventArgs
Dim value As String
 
instance.ClientId = value
 
value = instance.ClientId

[JetBrains.Annotations.NotNull()]
public string ClientId {get; set;}

[JetBrains.Annotations.NotNull()]
public:
property String^ ClientId {
   String^ get();
   void set (    String^ value);
}

Property Value

The value of this property cannot be null (Nothing in Visual Basic).

The default value of this property is "" (String.Empty).

This is the effective client ID (i.e. it contains the auto-generated client ID if no client ID was specified).

There are limitations to the MQTT client ID as defined by the MQTT protocol specification. These limitations ensure that the client ID is valid and can be used effectively by the MQTT broker. Here are the key constraints:

1. Length
   • MQTT 3.1.1: The client ID must be between 1 and 23 characters in length. If the client ID exceeds this length, the broker will reject the connection.
   • MQTT 5.0: The client ID can be up to 65535 characters in length. However, brokers may impose their own limits, so it's best to keep the client ID reasonably short.
2. Uniqueness
   • The client ID must be unique across all clients connected to the same broker. If two clients use the same client ID, the broker will disconnect the existing client when the new one connects.
3. Allowed Characters
   • In MQTT 5.0, the client ID can include any UTF-8 encoded characters. However, it is recommended to use alphanumeric characters and avoid special characters to ensure compatibility with all brokers. In MQTT 3.1.1, only the characters "0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ" can be used.

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Target Platforms: .NET Framework: Windows 10 (selected versions), Windows 11 (selected versions), Windows Server 2016, Windows Server 2022; .NET: Linux, macOS, Microsoft Windows