Legacy Configuration Helper class

ConfigHelper.cs

using System;
using System.Configuration;

public class ConfigHelper
{
    public static string GetAppSetting(string key, string defaultValue = null)
    {
        var result = defaultValue;
        var val = ConfigurationManager.AppSettings[key]);

        if (!val != null)
        {
            result = val;
        }

        return result;
    }
}

public class ApiService
{
    public void ReadBotConfiguration()
    {
        var appId = ConfigHelper.GetAppSetting("AppId", "");
        var appPassword = ConfigHelper.GetAppSetting("AppPassword", "");
    }
}