1. IronWebScraper
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  3. Advanced Webscraping Features

Advanced Webscraping Features

C# NuGet Library for

Install with NuGet

Install-Package IronWebScraper
nuget.org/packages/IronWebScraper/
or
C# DLL

Download DLL

Download DLL

Manually install into your project

HttpIdentity Feature

Some website systems require the user to be logged in to view the content; in this case we can use a HttpIdentity: -

HttpIdentity id = new HttpIdentity();
id.NetworkUsername = "username";
id.NetworkPassword = "pwd";
Identities.Add(id); 
HttpIdentity id = new HttpIdentity();
id.NetworkUsername = "username";
id.NetworkPassword = "pwd";
Identities.Add(id); 
Dim id As New HttpIdentity()
id.NetworkUsername = "username"
id.NetworkPassword = "pwd"
Identities.Add(id)
VB   C#

One of the most impressive and powerful features in IronWebScraper, is the ability to use thousands of unique (user’s credentials and/or browser engines) to spoof or scrape websites using multi login sessions.

public override void Init()
{
    License.LicenseKey = " LicenseKey ";
    this.LoggingLevel = WebScraper.LogLevel.All;
    this.WorkingDirectory = AppSetting.GetAppRoot() + @"\ShoppingSiteSample\Output\";
    var proxies = "IP-Proxy1: 8080,IP-Proxy2: 8081".Split(',');
    foreach (var UA in IronWebScraper.CommonUserAgents.ChromeDesktopUserAgents)
    {
        foreach (var proxy in proxies)
        {
            Identities.Add(new HttpIdentity()
            {
                UserAgent = UA,
                UseCookies = true,
                Proxy = proxy
            });
        }
    }
    this.Request("http://www.Website.com", Parse);
}
public override void Init()
{
    License.LicenseKey = " LicenseKey ";
    this.LoggingLevel = WebScraper.LogLevel.All;
    this.WorkingDirectory = AppSetting.GetAppRoot() + @"\ShoppingSiteSample\Output\";
    var proxies = "IP-Proxy1: 8080,IP-Proxy2: 8081".Split(',');
    foreach (var UA in IronWebScraper.CommonUserAgents.ChromeDesktopUserAgents)
    {
        foreach (var proxy in proxies)
        {
            Identities.Add(new HttpIdentity()
            {
                UserAgent = UA,
                UseCookies = true,
                Proxy = proxy
            });
        }
    }
    this.Request("http://www.Website.com", Parse);
}
Public Overrides Sub Init()
	License.LicenseKey = " LicenseKey "
	Me.LoggingLevel = WebScraper.LogLevel.All
	Me.WorkingDirectory = AppSetting.GetAppRoot() & "\ShoppingSiteSample\Output\"
	Dim proxies = "IP-Proxy1: 8080,IP-Proxy2: 8081".Split(","c)
	For Each UA In IronWebScraper.CommonUserAgents.ChromeDesktopUserAgents
		For Each proxy In proxies
			Identities.Add(New HttpIdentity() With {
				.UserAgent = UA,
				.UseCookies = True,
				.Proxy = proxy
			})
		Next proxy
	Next UA
	Me.Request("http://www.Website.com", Parse)
End Sub
VB   C#

You have multiple properties to give you different behaviors, so preventing websites from blocking you.

Some of these properties: -

  • NetworkDomain : The network domain to be used for user authentication. Supports Windows, NTLM , Keroberos, Linux, BSD and Mac OS X networks. Must be used with (NetworkUsername and NetworkPassword)
  • NetworkUsername : The network/http username to be used for user authentication. Supports Http, Windows networks, NTLM , Kerberos , Linux networks, BSD networks and Mac OS.
  • NetworkPassword : The network/http password to be used for user authentication. Supports Http , Windows networks, NTLM , Keroberos , Linux networks, BSD networks and Mac OS.
  • Proxy : to set proxy settings
  • UserAgent : to set browser engine (chrome desktop , chrome mobile , chrome tablet , IE and Firefox , etc.)
  • HttpRequestHeaders : for custom header values that will be used with this identity , and it accept dictionary object (Dictionary <string, string>)
  • UseCookies : enable/disable using cookies

IronWebScraper runs the scraper using random identities. If we need to specify the use of a specific identity to parse a page we can do so.

public override void Init()
{
    License.LicenseKey = " LicenseKey ";
    this.LoggingLevel = WebScraper.LogLevel.All;
    this.WorkingDirectory = AppSetting.GetAppRoot() + @"\ShoppingSiteSample\Output\";
    HttpIdentity identity = new HttpIdentity();
    identity.NetworkUsername = "username";
    identity.NetworkPassword = "pwd";
    Identities.Add(id);
    this.Request("http://www.Website.com", Parse, identity);
}
public override void Init()
{
    License.LicenseKey = " LicenseKey ";
    this.LoggingLevel = WebScraper.LogLevel.All;
    this.WorkingDirectory = AppSetting.GetAppRoot() + @"\ShoppingSiteSample\Output\";
    HttpIdentity identity = new HttpIdentity();
    identity.NetworkUsername = "username";
    identity.NetworkPassword = "pwd";
    Identities.Add(id);
    this.Request("http://www.Website.com", Parse, identity);
}
Public Overrides Sub Init()
	License.LicenseKey = " LicenseKey "
	Me.LoggingLevel = WebScraper.LogLevel.All
	Me.WorkingDirectory = AppSetting.GetAppRoot() & "\ShoppingSiteSample\Output\"
	Dim identity As New HttpIdentity()
	identity.NetworkUsername = "username"
	identity.NetworkPassword = "pwd"
	Identities.Add(id)
	Me.Request("http://www.Website.com", Parse, identity)
End Sub
VB   C#

Enable the Web Cache Feature

This feature is used to cache Requested Pages. It is often used in development and testing phases; enabling developers to cache required pages for reuse after updating code. This enables you to execute your code on cached pages after restarting your Web scraper and not needing to connect to the live website every time (action-replay).

You can use it in Init() Method

EnableWebCache();

OR

EnableWebCache(Timespan Expiry);

It will save your cached data to the WebCache folder under the working directory folder

public override void Init()
{
    License.LicenseKey = " LicenseKey ";
    this.LoggingLevel = WebScraper.LogLevel.All;
    this.WorkingDirectory = AppSetting.GetAppRoot() + @"\ShoppingSiteSample\Output\";
    EnableWebCache(new TimeSpan(1,30,30));
    this.Request("http://www.WebSite.com", Parse);
}
public override void Init()
{
    License.LicenseKey = " LicenseKey ";
    this.LoggingLevel = WebScraper.LogLevel.All;
    this.WorkingDirectory = AppSetting.GetAppRoot() + @"\ShoppingSiteSample\Output\";
    EnableWebCache(new TimeSpan(1,30,30));
    this.Request("http://www.WebSite.com", Parse);
}
Public Overrides Sub Init()
	License.LicenseKey = " LicenseKey "
	Me.LoggingLevel = WebScraper.LogLevel.All
	Me.WorkingDirectory = AppSetting.GetAppRoot() & "\ShoppingSiteSample\Output\"
	EnableWebCache(New TimeSpan(1,30,30))
	Me.Request("http://www.WebSite.com", Parse)
End Sub
VB   C#

IronWebScraper also has features to enable your engine to continue scraping after restarting code by setting the engine start process name using Start(CrawlID)

static void Main(string[] args)
{
    // Create Object From Scraper class
    EngineScraper scrape = new EngineScraper();
    // Start Scraping
    scrape.Start("enginestate");
}
static void Main(string[] args)
{
    // Create Object From Scraper class
    EngineScraper scrape = new EngineScraper();
    // Start Scraping
    scrape.Start("enginestate");
}
Shared Sub Main(ByVal args() As String)
	' Create Object From Scraper class
	Dim scrape As New EngineScraper()
	' Start Scraping
	scrape.Start("enginestate")
End Sub
VB   C#

The execution request and response will be saved in the SavedState folder inside the working directory.

Throttling

We can control the minimum and maximum connection numbers and connection speed per domain.

public override void Init()
{
    License.LicenseKey = "LicenseKey";
    this.LoggingLevel = WebScraper.LogLevel.All;
    this.WorkingDirectory = AppSetting.GetAppRoot() + @"\ShoppingSiteSample\Output\";
    // Gets or sets the total number of allowed open HTTP requests (threads)
    this.MaxHttpConnectionLimit = 80;
    // Gets or sets minimum polite delay (pause)between request to a given domain or IP address.
    this.RateLimitPerHost = TimeSpan.FromMilliseconds(50);            
    //     Gets or sets the allowed number of concurrent HTTP requests (threads) per hostname
    //     or IP address. This helps protect hosts against too many requests.
    this.OpenConnectionLimitPerHost = 25;
    this.ObeyRobotsDotTxt = false;
    //     Makes the WebSraper intelligently throttle requests not only by hostname, but
    //     also by host servers' IP addresses. This is polite in-case multiple scraped domains
    //     are hosted on the same machine.
    this.ThrottleMode = Throttle.ByDomainHostName;
    this.Request("https://www.Website.com", Parse);
}
public override void Init()
{
    License.LicenseKey = "LicenseKey";
    this.LoggingLevel = WebScraper.LogLevel.All;
    this.WorkingDirectory = AppSetting.GetAppRoot() + @"\ShoppingSiteSample\Output\";
    // Gets or sets the total number of allowed open HTTP requests (threads)
    this.MaxHttpConnectionLimit = 80;
    // Gets or sets minimum polite delay (pause)between request to a given domain or IP address.
    this.RateLimitPerHost = TimeSpan.FromMilliseconds(50);            
    //     Gets or sets the allowed number of concurrent HTTP requests (threads) per hostname
    //     or IP address. This helps protect hosts against too many requests.
    this.OpenConnectionLimitPerHost = 25;
    this.ObeyRobotsDotTxt = false;
    //     Makes the WebSraper intelligently throttle requests not only by hostname, but
    //     also by host servers' IP addresses. This is polite in-case multiple scraped domains
    //     are hosted on the same machine.
    this.ThrottleMode = Throttle.ByDomainHostName;
    this.Request("https://www.Website.com", Parse);
}
Public Overrides Sub Init()
	License.LicenseKey = "LicenseKey"
	Me.LoggingLevel = WebScraper.LogLevel.All
	Me.WorkingDirectory = AppSetting.GetAppRoot() & "\ShoppingSiteSample\Output\"
	' Gets or sets the total number of allowed open HTTP requests (threads)
	Me.MaxHttpConnectionLimit = 80
	' Gets or sets minimum polite delay (pause)between request to a given domain or IP address.
	Me.RateLimitPerHost = TimeSpan.FromMilliseconds(50)
	'     Gets or sets the allowed number of concurrent HTTP requests (threads) per hostname
	'     or IP address. This helps protect hosts against too many requests.
	Me.OpenConnectionLimitPerHost = 25
	Me.ObeyRobotsDotTxt = False
	'     Makes the WebSraper intelligently throttle requests not only by hostname, but
	'     also by host servers' IP addresses. This is polite in-case multiple scraped domains
	'     are hosted on the same machine.
	Me.ThrottleMode = Throttle.ByDomainHostName
	Me.Request("https://www.Website.com", Parse)
End Sub
VB   C#

Throttling properties

  • MaxHttpConnectionLimit
    Total number of allowed open HTTP requests (threads)
  • RateLimitPerHost
    Minimum polite delay or pause (in milliseconds) between request to a given domain or IP address
  • OpenConnectionLimitPerHost
    Allowed number of concurrent HTTP requests (threads)
  • ThrottleMode
    Makes the WebSraper intelligently throttle requests not only by hostname, but also by host servers' IP addresses. This is polite in-case multiple scraped domains are hosted on the same machine
.NET Software Engineer For many this is the most efficient way to generate PDF files from .NET, because there is no additional API to learn, or complex design system to navigate

Ahmed Aboelmagd

.NET Software Solution Architect at an Multinational IT Company

Ahmed is an experienced and certified Microsoft Technology specialist with more than 10 years experience in IT and Software development. He's worked in a range of companies, and is now a country manager for multinational IT Company.

Ahmed has been working with IronPDF and IronWebScraper for over a year now, using them in multiple projects with his company.