How do I test multiple browsers with selenium and a single NUnit suite and keep it DRY?

Question

I'm looking for a way to reuse one NUnit test suite without duplicating the entire suite for each browser. It seems like I would need a new fixture for each browser. Can I send some sort of environment variable or configuration setting from the NUnit gui to switch the browser? see below:

[TestFixture]
public class User
{
    private ISelenium selenium;
    private StringBuilder verificationErrors;

    [SetUp]
    public void SetupTest()
    {
        // TheBrowser = How do I populate this variable from the NUnit gui? 
        selenium = new DefaultSelenium("localhost", 4444, **TheBrowser**, "http://localhost:52251/");
        selenium.Start();
        verificationErrors = new StringBuilder();
    }

    [TearDown]
    public void TeardownTest()
    {
      ...
    }

    [Test]
    public void SearchUser()
    {
       ... 
    }

}

Answer 1

NUnit 2.5+ supports Generic Test Fixtures which make testing in multiple browsers very straightforward. http://www.nunit.org/index.php?p=testFixture&r=2.5

Building the following will create two "GoogleTest" NUnit tests, one for Firefox and one for IE.

using NUnit.Framework;
using OpenQA.Selenium;
using OpenQA.Selenium.Firefox;
using OpenQA.Selenium.IE;
using System.Threading;

namespace SeleniumTests 
{
    [TestFixture(typeof(FirefoxDriver))]
    [TestFixture(typeof(InternetExplorerDriver))]
    public class TestWithMultipleBrowsers<TWebDriver> where TWebDriver : IWebDriver, new()
    {
        private IWebDriver driver;

        [SetUp]
        public void CreateDriver () {
            this.driver = new TWebDriver();
        }

        [Test]
        public void GoogleTest() {
            driver.Navigate().GoToUrl("http://www.google.com/");
            IWebElement query = driver.FindElement(By.Name("q"));
            query.SendKeys("Bread" + Keys.Enter);

            Thread.Sleep(2000);

            Assert.AreEqual("bread - Google Search", driver.Title);
            driver.Quit();
        }
    }
}