![]() ![]() Here’s a helpful table of comparisons from Slotix’s Git Repo: Goal So instead of selecting a class or ID, we would create a path to the element itself. XML Path (XPath) uses xpath expressions to select nodes from an XML or HTML document. We can use the same logic to pick elements from the page using our scraper by defining the element + class (‘a.className’) or element + ID (‘a#idName’)Īn alternative to CSS selectors is using the XPath of the element. In other words, we’re selecting all elements with the class=”blog-detail-img-top” and applying the underneath styling. In the example above, the dot (.) represents ‘class’. These attributes are used to differentiate common tags from each other that can later be selected using Cascading Style Sheets (CSS) selectors and style them. If we look at the elements, we can see that each component has a class or an ID. So how do we tell our scraper which element to find and return? CSS and XPath Selectors If we just target the tag, we’ll be scraping a lot of unnecessary information (wasting time and resources). Of course, every website is built differently, so spending some time understanding the logic of a site is really important to avoid bottlenecks later on.Ī common occurrence is that the pages use the same HTML tags for different elements. It seems the title is wrapped around a tag inside an. From the Inspector tool, click on the title, and the console will jump to that element. Let’s say that we want the title of this article. This will help us find each element’s source code and understand how to make our scraper find it. We’re now inside the Inspector or the browser’s Developer Tools. To take a look at the HTML structure of a website, hit Ctrl/Command + Shift + C (or right-click and hit inspect) on the page you want to scrape. Also, we can target the href attribute to get the URL this is especially important for storing the data source or following paginations. In some cases, titles are wrapped inside tags, so we’ll need to extract the text from the link to access them. a – tells the browser the element is a link targetting another page (internal or external).Between these tags, we can usually find descriptions, listing details, and even prices. p – defines an element like a paragraph.In some cases, we want to get a specific to tell our scraper where to look for an element. div – it specifies a section of a page and is used to organized the content. ![]() We usually scrape these elements to get product names, content titles, and news headlines. H1 to 6 – defines headings in a descending hierarchy.This tells the browser this is the most important heading on the page Every website uses HTML to tell the browser how to render its content by wrapping each element between tags. Hypertext Markup Language (HTML) is the basic block of the web. Let’s do a brief overview of this structure – if you’re already familiar with HTML and CSS, you can move to the next section. HTML and CSS Basics for Web Scraping in C#īefore we can write any code, we first need to understand the website we want to get data from, paying particular attention to the HTML structure and the CSS selectors. These frameworks make sending HTTP requests and parse the DOM easy and clean, and we’ll thank a clean code when it’s time to maintain our scraper. NET Core to build a functional web scraper in a fraction of the time using tools like ScrapySharp and HtmlAgilityPack. There’s no point in committing to a tool that makes our job harder, is it? When choosing a language to build our web scraper, we’re looking for simplicity and scalability. However, using C for web scraping can be both expensive and inefficient.īuilding a C web scraper would have us creating many components from scratch or writing long, convoluted code files to do simple functions. Why Use C# Instead of C for Web Scraping?Ĭ is a widely used mid-level programming language capable of build operating systems and program applications. However, there are a few things we need to cover before we start writing our code. Plus, we’ll teach you how to avoid getting your bot blocked with a simple line of code. In this tutorial, we’ll create a simple web scraper using C# and its easy-to-use scraping libraries. C# is a general-purpose programming language that is mainly used in enterprise projects and applications, with roots in the C family – making it a highly efficient language to have in your tool belt.īecause of its popularity, C# has a vast set of tools that allow developers to implement elegant solutions, and web scraping isn’t the exception. ![]()
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