![]() ![]() Selects all preceding siblings of type, e.g. following-sibling::div will select all div siblings below the current node Selects all following siblings of type, e.g. Select current node (this is useful as argument in xpath function, we'll cover more later) Selector constraint - can be used to filter out nodes that do no match some condition will select value of href attribute of an a node Wildcard can be used instead of node an attribute of a node e.g. Selects any descendant - child, grandchild, gran-grandchild etc. Selects a direct child that matches node name. Let's see the most commonly used expressions in this XPath cheat sheet: expression Xpath selectors are made up of multiple expressions joined together into a single string. In this example, XPath would select href attribute of an node that has a class "button" which is also directly under node: It's a rather unique path language, so let's start off with a quick glance over basic syntax.Īverage xpath selector in web scraping often looks something like this: illustration of a usual xpath selector's structure Xpath selectors are usually referred to as "xpaths" and a single xpath indicates a destination from the root to the desired endpoint. Now that we're familiar with HTML let's familiarize ourselves with Xpath itself! Xpath Syntax Overview Here we can wrap our heads around it a bit more easily: it's a tree of nodes and each node can also have properties attached to them like keyword attributes (like class and href) and natural attributes such as text. Let's go a bit further and illustrate this: HTML tree is made of nodes which can contain attributes such as classes, ids and text itself. In this basic example of a simple web page, we can see that the document already resembles a data tree. Let's start off with a small example page and illustrate its structure: In other words, HTML follows a tree-like structure of nodes and their attributes, which we can easily navigate programmatically. ![]() HTML (HyperText Markup Language) is designed to be easily machine-readable and parsable. Xpath is easily extendable with additional functionality.īefore we dig into Xpath let's have a quick overview of HTML itself and how it enables xpath language to find anything with the right instructions.Xpath can transform results before returning them.Xpath can traverse HTML trees in every direction and is location-aware.Other path languages you might know of are CSS selectors which usually describe paths for applying styles, or tool-specific languages like jq which describe paths for JSON-type documents.įor HTML parsing, Xpath has some advantages over CSS selectors: XPath stands for "XML Path Language" which essentially means it's a query language that described a path from point A to point B for XML/HTML type of documents. We'll start with a quick introduction and expression cheatsheet and explore concepts using an interactive XPath tester.įinally, we'll wrap up by covering XPath implementations in various programming languages and some common idioms and tips when it comes to XPath in web scraping. ![]() In this article, we'll be taking a deep look at this unique path language and how can it be used to extract needed details from modern, complex HTML documents. ![]()
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