How do I extract data from a website using javascript.

问题

Hi complete newbie here so bear with me. Seems like a simple job but I can't seem to find an easy way to do this.

So I need to extract a particular text from a webpage "www.example.com/index.php". I know that the text would be available in p tag with certain id. How do I extract this data out using javascript?

What I'm trying currently is that I have my javascript file (trying.js) on my computer with the following code:

$(document).ready(function () {
    $.get("www.example.com/index.php", function(data) {
        console.log(data)
    }) ;
});

and a html that runs the javascript file.

When I open this html page with firefox it doesn't show me anything in console. How do I get the website's data? Am I on the correct track here? Is there a better way to do this?

回答1:

What you're looking for is a page scraper. Javascript can't pull it off because it can only gather data from the domain you're on.

You could build it in Ruby, for example, and use one of the many existing gems for this sort of task, like https://github.com/assaf/scrapi or http://nokogiri.org/

回答2:

Please take a look at Can Javascript read the source of any web page?

There are multiple ways discussed. Hope it helps you.

来源：https://stackoverflow.com/questions/19181901/how-do-i-extract-data-from-a-website-using-javascript