# MTDevice Events #### OnDeviceList This event occurs when device information is available. ``` public event DeviceListHandler OnDeviceList public delegate void DeviceListHandler(object sender, MTConnectionType connectionType, List deviceList) ```


Parameter	Description
Sender	Object representing the publisher of the event.
connectionType	MTConnectionType value: MTConnectionType.USB, MTConnectionType.IP, MTConnectionType.Serial
deviceList	A list of MTDeviceInformation objects

#### OnDeviceConnectionStateChanged This event occurs when the connection state of the device is changed. ``` public event DeviceListHandler OnDeviceList public delegate void DeviceListHandler(object sender, MTConnectionType connectionType, List deviceList) ```

Parameter

Description

sender

Object representing the publisher of the event.

state

MTDeviceState value indicating the state of the device:

Disconnected Connecting Error Connected Disconneting

#### OnDeviceDataString This event occurs when a response is received from the device. ``` public event DeviceDataStringHandler OnDeviceDataString public delegate void DeviceDataStringHandler(object sender, string dataString) ```


Parameter	Description
sender	Object representing the publisher of the event.
dataString	Hexadecimal string representing data received.

#### OnDeviceDataBytes This event occurs when a response is received from the device. ``` public event DeviceDataBytesHandler OnDeviceDataBytes public delegate void DeviceDataBytesHandler(object sender, byte[] dataBytes) ```


Parameter	Description
sender	Object representing the publisher of the event.
dataBytes	Byte array representing data received.

#### OnDeviceResponseMessage This event occurs when a response is received from the device. ``` public event DeviceResponseMessageHandler OnDeviceResponseMessage public delegate void DeviceResponseMessageHandler(object sender, MTCMSResponseMessage response) ```


Parameter	Description
sender	Object representing the publisher of the event.
response	MTCMSResponseMessage representing data received.

#### OnDeviceNotificationMessage This event occurs when a response is received from the device. ``` public event DeviceNotificationMessageHandler OnDeviceNotificationMessage public delegate void DeviceNotificationMessageHandler(object sender, MTCMSNotificationMessage notification) ```


Parameter	Description
sender	Object representing the publisher of the event.
notification	MTCMSNotificationMessage representing data received.

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