You could be more specific and look for all “a” elements within a certain area of the web page. This means all the links in the menus, any jump links that take you to different points on the current page, the contact, T&Cs, sitemap links at the base of the page, etc… There is a drawback to the current code - it will take ALL of the links on a page. We then open a new window using “window.open()” and write the HTML table to that window using “document.write()”. We then use a for loop to add table rows containing the link text and hyperlinks. This creates a variable, table, with the beginnings of a HTML table and the table headers. We then make the table using the function “make_table()”. for (var i=0 iNameLinks' for (var i=0 i'+ myarray + ''+myarray+'' } var w = window.open("") w.document.write(table) } make_table() Then we create an array variable, but leave it empty for now. Here we are finding all of the “a” elements on the page (a elements are links) and assigning them to the variable x. var x = document.querySelectorAll("a") var myarray = Here is a breakdown of the code and what each aspect does. This table can then be copied and pasted into a spreadsheet or document to be used as you please. How the table appears once the code runs. This will open up a new tab in your browser with a table containing all the link text and hyperlinks from your chosen web page. Then just hit enter (or the run button in IE. This is the code snippet you will need to place into the console: var x = document.querySelectorAll("a") var myarray = for (var i=0 iNameLinks' for (var i=0 i'+ myarray + ''+myarray+'' } var w = window.open("") w.document.write(table) } make_table() This will open up the console, into which you can type or copy and paste snippets of code. To open the developer console, you can either hit F12 or right-click the page and select “Inspect” or ”Inspect Element” depending on your browser of choice. Now we just need to open up the developer console and run the code. I’m using the Select Committee inquiries list from the 2017 Parliament page as an example - it is a page with a massive amount of links that, as a grouping, may be useful to a lot of people. Select Committee inquiries from the 2017 Parliament Open up your browser (yes, this even works in Internet Explorer if you’re a glutton for punishment) and navigate to the page from which you’d like to extract links. The bit of code I’ll be providing further down the page.Literally any browser made in the past 10 years. When this code runs, it opens a new tab in the browser and outputs a table containing the text of each hyperlink and the link itself, so there is some context to what each link is pointing to. However, this code would work equally well to extract any other text element types in HTML documents, with a few small changes. In this example, I am extracting all links from a web page, as this is a task I regularly perform on web pages. Regular old JavaScript is powerful enough to extract information from a single web page, and the JavaScript in question can be run in the browser’s developer console. This is using a sledgehammer to crack a nut. Previously when a case like this arose, I would still fire up my Python IDE or RStudio, write and execute a script to extract this information. But sometimes a project only needs a small amount of data, from just one page on a website. Using the console to extract links from a web pageĮxtracting and cleaning data from websites and documents is my bread and butter and I have really enjoyed learning how to systematically extract data from multiple web pages and even multiple websites using Python and R.
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