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c#.netwindowsbluetoothpairing

How to "unpair", "remove" Bluetooth device in Windows with C# .NET

I faced a problem. I need to unpair, or remove bluetooth device from windows. Here, I have my phone Redmi paired

enter image description here

And I need to unpair it, so basically I want to achieve the same effect as pressing "Remove device" button

I tried this, but it didn't work for me, since this solution disconnects bluetooth device, but it still stays paired: How to disconnect a bluetooth device from C# .Net in Win7

I am using C# WPF and InTheHand library for pairing, but it does not have unpair functionality

How do I achieve my goal? Thank

Solution

  • To unapir classic Bluetooth device you have to call BluetoothRemoveDevice function.

    For .NET it can be imported as below

    [StructLayout(LayoutKind.Explicit)]
struct BLUETOOTH_ADDRESS
{
  [FieldOffset(0)]
  [MarshalAs(UnmanagedType.I8)]
  public Int64 ullLong;
  [FieldOffset(0)]
  [MarshalAs(UnmanagedType.U1)]
  public Byte rgBytes_0;
  [FieldOffset(1)]
  [MarshalAs(UnmanagedType.U1)]
  public Byte rgBytes_1;
  [FieldOffset(2)]
  [MarshalAs(UnmanagedType.U1)]
  public Byte rgBytes_2;
  [FieldOffset(3)]
  [MarshalAs(UnmanagedType.U1)]
  public Byte rgBytes_3;
  [FieldOffset(4)]
  [MarshalAs(UnmanagedType.U1)]
  public Byte rgBytes_4;
  [FieldOffset(5)]
  [MarshalAs(UnmanagedType.U1)]
  public Byte rgBytes_5;
};

[DllImport("BluetoothAPIs.dll", SetLastError = true, CallingConvention = CallingConvention.StdCall)]
[return: MarshalAs(UnmanagedType.U4)]
static extern UInt32 BluetoothRemoveDevice(
  [param: In, Out] ref BLUETOOTH_ADDRESS pAddress);

    Here is how to call it:

    UInt32 Unpair(Int64 Address)
{
  BLUETOOTH_ADDRESS Addr = new BLUETOOTH_ADDRESS();
  Addr.ullLong = Address;
  return BluetoothRemoveDevice(ref Addr);
}

    Please not that this function allows to unpair Classic Bluetooth devices only. To unpair Bluetooth LE devices you have to use other way based on WinRT.