What design patterns are applicable in automated testing?

In automated testing with C#, the following design patterns are often used:

• Page Object — for organizing interaction with UI elements, improving test support and readability.
• Factory — for creating test data objects or components, simplifying test configuration.
• Singleton — for managing shared resources, such as browser drivers.
• Decorator — for extending the functionality of test objects without modifying their code.
• Strategy — for selecting different algorithms or methods of executing tests depending on conditions.

Example of using Page Object:

public class LoginPage {
    private IWebDriver driver;
    public LoginPage(IWebDriver driver) {
        this.driver = driver;
    }
    public void EnterUsername(string username) {
        driver.FindElement(By.Id("username")).SendKeys(username);
    }
    public void EnterPassword(string password) {
        driver.FindElement(By.Id("password")).SendKeys(password);
    }
    public void ClickLogin() {
        driver.FindElement(By.Id("loginButton")).Click();
    }
}

This approach facilitates support and scaling of tests.