private void OnDiscoveredPeripheral(object sender, CBDiscoveredPeripheralEventArgs e)
{
var device = new BLEDevice(_managerWrapper, e.Peripheral);
var rssi = e.RSSI.Int32Value;
var advertisements = BLEAdvertisement.Parse(e.AdvertisementData);
RaiseDeviceDiscovered(device, rssi, advertisements);
}
public static IList <BLEAdvertisement> Parse(NSDictionary value)
{
var advertisements = new List <BLEAdvertisement>();
foreach (var o in value.Keys)
{
var key = (NSString)o;
if (key == CBAdvertisement.DataLocalNameKey)
{
var data = NSData.FromString((NSString)value.ObjectForKey(key)).ToArray();
var item = new BLEAdvertisement(BLEAdvertisementType.CompleteLocalName, data);
advertisements.Add(item);
}
else if (key == CBAdvertisement.DataManufacturerDataKey)
{
var data = ((NSData)value.ObjectForKey(key)).ToArray();
var item = new BLEAdvertisement(BLEAdvertisementType.ManufacturerSpecificData, data);
advertisements.Add(item);
}
else if (key == CBAdvertisement.DataServiceUUIDsKey)
{
var array = (NSArray)value.ObjectForKey(key);
var datas = new List <NSData>();
for (nuint i = 0; i < array.Count; i++)
{
var uuid = array.GetItem <CBUUID>(i);
datas.Add(uuid.Data);
}
var data = datas.SelectMany(d => d.ToArray()).ToArray();
var item = new BLEAdvertisement(BLEAdvertisementType.CompleteServiceUUIDs128Bit, data);
advertisements.Add(item);
}
else if (key == CBAdvertisement.DataTxPowerLevelKey)
{
//iOS stores TxPower as NSNumber. Get int value of number and convert it into a signed Byte
//TxPower has a range from -100 to 20 which can fit into a single signed byte (-128 to 127)
var byteValue = Convert.ToSByte(((NSNumber)value.ObjectForKey(key)).Int32Value);
//add our signed byte to a new byte array and return it (same parsed value as android returns)
var data = new byte[] { (byte)byteValue };
var item = new BLEAdvertisement(BLEAdvertisementType.TxPowerLevel, data);
advertisements.Add(item);
}
else if (key == CBAdvertisement.DataServiceDataKey)
{
//Service data from CoreBluetooth is returned as a key/value dictionary with the key being
//the service uuid (CBUUID) and the value being the NSData (bytes) of the service
//This is where you'll find eddystone and other service specific data
var datas = (NSDictionary)value.ObjectForKey(key);
//There can be multiple services returned in the dictionary, so loop through them
foreach (CBUUID dataKey in datas.Keys)
{
//Get the service key in bytes (from NSData)
var keyData = dataKey.Data.ToArray();
//Service UUID's are read backwards (little endian) according to specs,
//CoreBluetooth returns the service UUIDs as Big Endian
//but to match the raw service data returned from Android we need to reverse it back
//Note haven't tested it yet on 128bit service UUID's, but should work
Array.Reverse(keyData);
//The service data under this key can just be turned into an arra
var dataValue = (NSData)datas.ObjectForKey(dataKey);
var valueData = dataValue.Length > 0 ? dataValue.ToArray() : new byte[0];
//Now we append the key and value data and return that so that our parsing matches the raw
//byte value returned from the Android library (which matches the raw bytes from the device)
var data = new byte[keyData.Length + valueData.Length];
Buffer.BlockCopy(keyData, 0, data, 0, keyData.Length);
Buffer.BlockCopy(valueData, 0, data, keyData.Length, valueData.Length);
var item = new BLEAdvertisement(BLEAdvertisementType.ServiceData, data);
advertisements.Add(item);
}
}
else if (key == CBAdvertisement.IsConnectable)
{
// A Boolean value that indicates whether the advertising event type is connectable.
// The value for this key is an NSNumber object. You can use this value to determine whether a peripheral is connectable at a particular moment.
var byteValue = ((NSNumber)value.ObjectForKey(key)).ByteValue;
var data = new byte[] { byteValue };
var item = new BLEAdvertisement(BLEAdvertisementType.IsConnectable, data);
advertisements.Add(item);
}
else
{
Debug.Write($"Parsing Advertisement: Ignoring Advertisement entry for key {key.ToString()}, since we don't know how to parse it yet. Maybe you can open a Pull Request and implement it :)");
}
}
return(advertisements);
}
public static IList <BLEAdvertisement> Parse(byte[] value)
{
var records = new List <BLEAdvertisement>();
var index = 0;
while (index < value?.Length)
{
var length = value[index++];
// Done once we run out of records
// 1 byte for type and length-1 bytes for data
if (length == 0)
{
break;
}
var type = (BLEAdvertisementType)value[index];
// Done if our record isn't a valid type
if (type == 0)
{
break;
}
// Advertisment record type not defined:
if (!Enum.IsDefined(typeof(BLEAdvertisementType), type))
{
Debug.WriteLine($"Advertisment record type not defined: {type}");
break;
}
//data length is length -1 because type takes the first byte
var data = new byte[length - 1];
Array.Copy(value, index + 1, data, 0, length - 1);
// don't forget that data is little endian so reverse
// Supplement to Bluetooth Core Specification 1
// NOTE: all relevant devices are already little endian, so this is not necessary for any type except UUIDs
switch (type)
{
case BLEAdvertisementType.CompleteServiceUUIDs128Bit:
case BLEAdvertisementType.CompleteServiceUUIDs16Bit:
case BLEAdvertisementType.CompleteServiceUUIDs32Bit:
case BLEAdvertisementType.IncompleteServiceUUIDs128Bit:
case BLEAdvertisementType.IncompleteServiceUUIDs16Bit:
case BLEAdvertisementType.IncompleteServiceUUIDs32Bit:
case BLEAdvertisementType.ServiceDataUUID128Bit:
case BLEAdvertisementType.ServiceDataUUID16Bit:
case BLEAdvertisementType.ServiceDataUUID32Bit:
case BLEAdvertisementType.ServiceSolicitationUUIDs128Bit:
case BLEAdvertisementType.ServiceSolicitationUUIDs16Bit:
case BLEAdvertisementType.ServiceSolicitationUUIDs32Bit:
Array.Reverse(data);
break;
}
var record = new BLEAdvertisement(type, data);
Debug.WriteLine(record.ToString());
records.Add(record);
// Advance
index += length;
}
return(records);
}