Running Multiple TestFixtures in One Browser Instance ( NUNIT, Visual Studio Test, Selenium, Webdriver )

mysetupclass.cs

//C# NUNIT 3.0 

/*
* Problem: Running multiple TestFixtures within one browser instance.
* you can create one dedicated setup class say MySetupClass where
* on RunBeforeANyTests method set your broser instance in some shared static class
* Say BrowserProvider class then in all of your TestFixture you can get your current broser instance from 
* This BrowserProvider class. 
*/ 

// MySetupClass.cs
using System;
using NUnit.Framework;

namespace NUnit.Tests
{
  [SetUpFixture]
  public class MySetUpClass
  {
	[OneTimeSetUp]
	public void RunBeforeAnyTests()
	{
	   
	}

	[OneTimeTearDown]
	public void RunAfterAnyTests()
	{
	  browsers.Close();
	}
  }
}
}



Ref: https://github.com/nunit/docs/wiki/SetUpFixture-Attribute

Running Multiple TestFixtures in One Browser Instance.cs

// You can drive your browsers from appsettings. And then in each TestFixture you just use this broswer settings. 
// One thing to note is dont quit browser on teardown. 
// Browsers.cs
public class Browsers
{
    private static IWebDriver webDriver;
    private static string baseURL = ConfigurationManager.AppSettings["url"];
    private static string browser = ConfigurationManager.AppSettings["browser"];
    public static void Init()
    {
         switch (browser)
         {
             case "Chrome":
                 webDriver = new ChromeDriver();
              break;
             case "IE":
                 webDriver = new InternetExplorerDriver();
             break;
             case "Firefox":
                 webDriver = new FirefoxDriver();
             break;
         }
         webDriver.Manage().Window.Maximize();
         Goto(baseURL);
    }
    public static string Title
    {
         get { return webDriver.Title; }
    }
    public static IWebDriver getDriver
    {
         get { return webDriver; }
    }
    public static void Goto(string url)
    {
         webDriver.Url = url;
    }
    public static void Close()
    {
         webDriver.Quit();
    }
}

Ref:https://blog.testproject.io/2017/02/09/cross-browser-testing-selenium-webdriver/