寻找一个IOS版的Xamarin.Forms蓝牙库，它可以接收已经配对的设备到我的iphone上。

在iOS上使用Xamarin.Forms开发蓝牙应用时，你可以考虑使用Plugin.BLE（Bluetooth Low Energy）插件。这是一个跨平台的解决方案，支持iOS、Android以及其他平台。它允许你扫描、连接、发现服务和读取/写入特征，适用于已经配对或未配对的设备。

以下是如何在Xamarin.Forms项目中使用Plugin.BLE的基本步骤：

安装NuGet包

首先，在你的Xamarin.Forms项目中安装Plugin.BLE NuGet包。

Install-Package Plugin.BLE

初始化蓝牙

在你的应用启动时初始化蓝牙插件。

using Plugin.BLE;
using Plugin.BLE.Abstractions.Contracts;

public class BluetoothManager
{
    private readonly IBluetoothManager _bluetoothManager;

    public BluetoothManager()
    {
        _bluetoothManager = CrossBluetoothLE.Current;
    }

    public async Task InitializeAsync()
    {
        var state = await _bluetoothManager.GetConnectionStateAsync();
        if (state != BluetoothConnectionState.Connected)
        {
            // Handle the case where the device is not connected
        }
    }
}

扫描设备

你可以扫描附近的蓝牙设备。

public async Task ScanForDevicesAsync()
{
    var devices = await _bluetoothManager.DiscoverDevicesAsync(10000); // 10 seconds scan time
    foreach (var device in devices)
    {
        // Handle each discovered device
    }
}

连接设备

连接到特定的蓝牙设备。

public async Task ConnectToDeviceAsync(Guid deviceId)
{
    var device = await _bluetoothManager.GetDeviceAsync(deviceId);
    await device.ConnectAsync();
}

发现服务和特征

一旦连接成功，你可以发现设备的服务和特征。

public async Task DiscoverServicesAndCharacteristicsAsync(Guid deviceId)
{
    var device = await _bluetoothManager.GetDeviceAsync(deviceId);
    var services = await device.DiscoverServicesAsync();
    foreach (var service in services)
    {
        var characteristics = await service.DiscoverCharacteristicsAsync();
        foreach (var characteristic in characteristics)
        {
            // Handle each characteristic
        }
    }
}

读取/写入特征

你可以读取或写入特征值。

public async Task ReadCharacteristicValueAsync(Guid deviceId, Guid serviceId, Guid characteristicId)
{
    var device = await _bluetoothManager.GetDeviceAsync(deviceId);
    var service = device.Services.FirstOrDefault(s => s.Id == serviceId);
    var characteristic = service.Characteristics.FirstOrDefault(c => c.Id == characteristicId);
    var value = await characteristic.ReadAsync();
}

public async Task WriteCharacteristicValueAsync(Guid deviceId, Guid serviceId, Guid characteristicId, byte[] value)
{
    var device = await _bluetoothManager.GetDeviceAsync(deviceId);
    var service = device.Services.FirstOrDefault(s => s.Id == serviceId);
    var characteristic = service.Characteristics.FirstOrDefault(c => c.Id == characteristicId);
    await characteristic.WriteAsync(value);
}