iOS corebluetooth数据发送问题

我正在使用corebluetooh api发送数据到蓝牙设备。 在Android上它的工作正常，但在iOS上它不工作。

我正在发送数据如下

public override void DiscoveredCharacteristic(CBPeripheral peripheral, CBService service, NSError error) { System.Console.WriteLine("Discovered characteristics of " + peripheral); foreach (var characteristic in service.Characteristics) { Console.WriteLine("Write Value of characteristic " + characteristic.ToString() + " is " + characteristic.Value); var str = characteristic.UUID.ToString(); if (str.ToLower() == "00C957FB-8F6F-4E08-9ACB-000000000004".ToLower()) { var hh1 = NSData.FromArray(new byte[] { 0x03, 0x1d, 0x00, 0x32, 0xb1, 0xc0 }); peripheral.WriteValue(hh1, characteristic, CBCharacteristicWriteType.WithResponse); } if (str.ToLower() == "00C957FB-8F6F-4E08-9ACB-000000000002".ToLower()) { var hh = NSData.FromArray(new byte[] { 3, 29, 0, 50, 177, 192 }); peripheral.WriteValue(hh, characteristic, CBCharacteristicWriteType.WithResponse); } }} 

在写入数据之后， WroteCharacteristicValue被调用，但在UpdatedCharacterteristicValue方法特性下。 值为空

请帮忙