如何实例化InternetExplorerDriver-Selenium 2的不同版本？

this.SetCapability(CapabilityType.BrowserName, \"internet explorer\");
this.SetCapability(CapabilityType.Version, \"8\");
this.SetCapability(CapabilityType.Platform, \"WINDOWS\");

DesiredCapabilities internetExplorer8 =
                          DesiredCapabilities.InternetExplorer().SetVersion(\"8\");
IWebDriver webDriver = new RemoteWebDriver(seleniumHubUrl, internetExplorer8);

public static class DesiredCapabilitiesExtension
{
    public static DesiredCapabilities SetBrowserName(this DesiredCapabilities desiredCapabilities, string browserName)
    {
        // make sure the browser name is lowercase
        desiredCapabilities.SetCapability(CapabilityType.BrowserName, browserName.ToLowerInvariant());
        return desiredCapabilities;
    }

    public static DesiredCapabilities SetVersion(this DesiredCapabilities desiredCapabilities, string version)
    {
        desiredCapabilities.SetCapability(CapabilityType.Version, version);
        return desiredCapabilities;
    }

    public static DesiredCapabilities SetPlatform(this DesiredCapabilities desiredCapabilities, string platform)
    {
        // make sure the platform is case sensitive, uppercase to make it work
        desiredCapabilities.SetCapability(CapabilityType.Platform, platform.ToUpperInvariant());
        return desiredCapabilities;
    }
}