iot: Dht22 example doesn't work

I have DHT22 sensors which works normally. I checked that by the default python script from Adafriut. I made a decision to give .net core on rpi platform a try with a simple example from the examples folder. I used Dhtxx example but it doesn’t work.

This is my code:

using System;
using System.Threading;
using Iot.Device.DHTxx;

class Program
{
    static void Main(string[] args)
    {
        Console.WriteLine("Hello DHT!");

        using (DhtSensor dht = new DhtSensor(26, DhtType.Dht22))
        {
            while (true)
            {
                Console.WriteLine($"Temperature: {dht.Temperature.Celsius} °C, Humidity: {dht.Humidity} %");

                Thread.Sleep(2000);
            }
        }
    }
}

Project file:

<Project Sdk="Microsoft.NET.Sdk">

  <PropertyGroup>
    <OutputType>Exe</OutputType>
    <TargetFramework>netcoreapp2.2</TargetFramework>
  </PropertyGroup>

  <ItemGroup>
    <PackageReference Include="IoT.Device.Bindings" Version="0.1.0-prerelease.19251.2" />
    <PackageReference Include="System.Device.Gpio" Version="0.1.0-prerelease.19251.2" />
  </ItemGroup>

</Project>

I wasn’t able to install System.Device.Gpio and IoT.Device.Bindings by using commands from the main readme.md so I just used the nearest proposed version by dotnet add.

I installed .net core on the rpi by using commands:

sudo apt-get install curl libunwind8 gettext
wget https://download.visualstudio.microsoft.com/download/pr/9650e3a6-0399-4330-a363-1add761127f9/14d80726c16d0e3d36db2ee5c11928e4/dotnet-sdk-2.2.102-linux-arm.tar.gz
wget https://download.visualstudio.microsoft.com/download/pr/9d049226-1f28-4d3d-a4ff-314e56b223c5/f67ab05a3d70b2bff46ff25e2b3acd2a/aspnetcore-runtime-2.2.1-linux-arm.tar.gz
mkdir -p $HOME/dotnet && tar zxf dotnet-sdk-2.2.102-linux-arm.tar.gz -C $HOME/dotnet
export DOTNET_ROOT=$HOME/dotnet 
export PATH=$PATH:$HOME/dotnet
tar zxf aspnetcore-runtime-2.2.1-linux-arm.tar.gz -C $HOME/dotnet

On top of that I wasn’t able to run it on rpi without dotnet publish -r linux-arm since I get FileNotFoundExceptions and runtime isn’t able to find System.Device.Gpio.

The result of the program:

pi@raspberrypi:~/publish $ dotnet test_dht22.dll
Hello DHT!
Temperature: NaN °C, Humidity: NaN %
Temperature: NaN °C, Humidity: NaN %
Temperature: NaN °C, Humidity: NaN %

I tried other library versions and sometimes got values like 123e-308.

Do I do something wrong or the project isn’t ready yet for real usage (only people with deep .net knowledge can use it)?