dotnet核心webapp没有gpio访问权限

Question

我正在尝试让一个aspnet核心get应用程序在我的树莓派上运行。这个应用程序使用Bifrost与树莓的GPIO进行交互，但是每次我执行sudo dotnet run时，它都会失败，并显示以下错误

Using launch settings from /home/pi/Desktop/keypad-alarm/keypad-alarm-server/Properties/launchSettings.json...     
Write value High to pin at /sys/class/gpio/gpio17/value

Unhandled Exception: System.UnauthorizedAccessException: Access to the path '/sys/class/gpio/gpio17/value' is denied. ---> System.IO.IOException: Operation not permitted    
--- End of inner exception stack trace ---    at 
System.IO.FileStream.WriteNative(ReadOnlySpan`1 source)    at 
System.IO.FileStream.FlushWriteBuffer()    at 
System.IO.FileStream.FlushInternalBuffer()    at 
System.IO.FileStream.Flush(Boolean flushToDisk)    at 
System.IO.FileStream.Flush()    at 
System.IO.StreamWriter.Flush(Boolean flushStream, Boolean flushEncoder)    at 
System.IO.StreamWriter.Dispose(Boolean disposing)  at 
System.IO.TextWriter.Dispose()   
 at System.IO.File.WriteAllText(String path, String contents)    at 
Bifrost.Devices.Gpio.GpioPin.Write(GpioPinValue pinValue)    at 
keypad_alarm_server.TweetController.Tweet(Int32 milliseconds) in 
/home/pi/Desktop/keypad-alarm/keypad-alarm-server/TweetController.cs:line 25    at 
keypad_alarm_server.Program.Main(String[] args) in /home/pi/Desktop/keypad-alarm/keypad-alarm-server/Program.cs:line 15

我应该提一下，在我启动Program.cs中的even服务器之前，我立即将GPIO17调到高电平以发出蜂鸣声。

如何确保dotnet有足够的权限访问gpio？

Answer 1

好的，像往常一样，在你花时间发布问题后，你会在某个地方找到答案……

pin.SetDriveMode(GpioPinDriveMode.Output);异常具有极大的误导性，因为遗漏了c#中的以下语句：

public class TweetController
{
    private static IGpioController _gpio = null;
    private const int PIN = 17;

    public TweetController()
    {
        _gpio = GpioController.Instance;
    }

    public void Tweet(int milliseconds){
        var pin = _gpio.OpenPin(PIN);
        pin.SetDriveMode(GpioPinDriveMode.Output); // open the gpio pin before writing or unauthorizedexception occurs
        pin.Write(GpioPinValue.High);
        Thread.Sleep(milliseconds);
        pin.Write(GpioPinValue.Low);
    }
}