SimpleBrowserDotNet / SimpleBrowser

A flexible and intuitive web browser engine designed for automation tasks. Built on .NET Standard 2.1.
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SimpleBrowser

SimpleBrowser is a lightweight, yet highly capable browser automation engine designed for automation and testing scenarios. It provides an intuitive API that makes it simple to quickly extract specific elements of a page using a variety of matching techniques, and then interact with those elements with methods such as Click(), SubmitForm() and many more. SimpleBrowser does not support JavaScript, but allows for manual manipulation of the user agent, referrer, request headers, form values and other values before submission or navigation.

Requirements

Features

Example

class Program
{
    static void Main(string[] args)
    {
        var browser = new Browser();
        try
        {
            // log the browser request/response data to files so we can interrogate them in case of an issue with our scraping
            browser.RequestLogged += OnBrowserRequestLogged;
            browser.MessageLogged += new Action<Browser, string>(OnBrowserMessageLogged);

            // we'll fake the user agent for websites that alter their content for unrecognised browsers
            browser.UserAgent = "Mozilla/5.0 (Windows; U; Windows NT 6.1; en-US) AppleWebKit/534.10 (KHTML, like Gecko) Chrome/8.0.552.224 Safari/534.10";

            // browse to GitHub
            browser.Navigate("http://github.com/");
            if(LastRequestFailed(browser)) return; // always check the last request in case the page failed to load

            // click the login link and click it
            browser.Log("First we need to log in, so browse to the login page, fill in the login details and submit the form.");
            var loginLink = browser.Find("a", FindBy.Text, "Login");
            if(!loginLink.Exists)
                browser.Log("Can't find the login link! Perhaps the site is down for maintenance?");
            else
            {
                loginLink.Click();
                if(LastRequestFailed(browser)) return;

                // fill in the form and click the login button - the fields are easy to locate because they have ID attributes
                browser.Find("login_field").Value = "youremail@domain.com";
                browser.Find("password").Value = "yourpassword";
                browser.Find(ElementType.Button, "name", "commit").Click();
                if(LastRequestFailed(browser)) return;

                // see if the login succeeded - ContainsText() is very forgiving, so don't worry about whitespace, casing, html tags separating the text, etc.
                if(browser.ContainsText("Incorrect login or password"))
                {
                    browser.Log("Login failed!", LogMessageType.Error);
                }
                else
                {
                    // After logging in, we should check that the page contains elements that we recognise
                    if(!browser.ContainsText("Your Repositories"))
                        browser.Log("There wasn't the usual login failure message, but the text we normally expect isn't present on the page");
                    else
                    {
                        browser.Log("Your News Feed:");
                        // we can use simple jquery selectors, though advanced selectors are yet to be implemented
                        foreach(var item in browser.Select("div.news .title"))
                            browser.Log("* " + item.Value);
                    }
                }
            }
        }
        catch(Exception ex)
        {
            browser.Log(ex.Message, LogMessageType.Error);
            browser.Log(ex.StackTrace, LogMessageType.StackTrace);
        }
        finally
        {
            var path = WriteFile("log-" + DateTime.UtcNow.Ticks + ".html", browser.RenderHtmlLogFile("SimpleBrowser Sample - Request Log"));
            Process.Start(path);
        }
    }

    static bool LastRequestFailed(Browser browser)
    {
        if(browser.LastWebException != null)
        {
            browser.Log("There was an error loading the page: " + browser.LastWebException.Message);
            return true;
        }
        return false;
    }

    static void OnBrowserMessageLogged(Browser browser, string log)
    {
        Console.WriteLine(log);
    }

    static void OnBrowserRequestLogged(Browser req, HttpRequestLog log)
    {
        Console.WriteLine(" -> " + log.Method + " request to " + log.Url);
        Console.WriteLine(" <- Response status code: " + log.ResponseCode);
    }

    static string WriteFile(string filename, string text)
    {
        var dir = new DirectoryInfo(Path.Combine(AppDomain.CurrentDomain.BaseDirectory, "Logs"));
        if(!dir.Exists) dir.Create();
        var path = Path.Combine(dir.FullName, filename);
        File.WriteAllText(path, text);
        return path;
    }
}