How to render part of a page with PhantomJS?

问题:

I would like to render individual HTML elements into PNGs using Phantom.JS. Does anyone know if this is possible? Also, how would I use Phantom.js to render a page that the user is already looking at?

回答1:

To only render part of a page you need to set the clipRect attribute for the page and then render it.

var clipRect = document.querySelector(selector).getBoundingClientRect();
page.clipRect = {
    top:    clipRect.top,
    left:   clipRect.left,
    width:  clipRect.width,
    height: clipRect.height
};
page.render('capture.png');

I don't understand the second part of your question. Phantom.js is headless meaning that there is no actual display that a user is looking at.

回答2:

Working example.

var page = require('webpage').create();

page.open('http://google.com', function() {
  // being the actual size of the headless browser
  page.viewportSize = { width: 1440, height: 900 };

  var clipRect = page.evaluate(function(){
    return document.querySelector('#hplogo').getBoundingClientRect();
  });

  page.clipRect = {
    top:    clipRect.top,
    left:   clipRect.left,
    width:  clipRect.width,
    height: clipRect.height
  };

  page.render('google.png');
  phantom.exit();
});

回答3:

You can use the CasperJS, another project based on PhantomJS.

casper.start('http://www.weather.com/', function() {
    this.captureSelector('weather.png', '#wx-main');
});

casper.run();

回答4:

The solution below works for me.

    var clipRect = document.querySelector(selector).getBoundingClientRect();
     page.clipRect = {
              top:    clipRect.top,
              left:   clipRect.left,
              width:  clipRect.width,
              height: clipRect.height
      };
   page.render('capture.png');

But I notice that this on works only if we are rendering an image not a pdf. To wokaround this for pdf, try this

page.evaluate(function (element){
    $(element).appendTo('body');
    $('body > :not(' + element + ')').hide(); 
   }, element);       
  });

window.setTimeout(function(){
    page.render("page.pdf");
  },1000);

This links may help: How to hide all elements except one using jquery?

https://github.com/ariya/phantomjs/issues/10465

回答5:

I had the same need, I tried this and it worked fine for me :

don't forget the http://www in the URL

var page = require('webpage').create();
page.open('YourPageURL', function (status) {

if (status !== 'success') {
    console.log('Network Problem');
} else {
    var p = page.evaluate(function () {
        return document.getElementById('yourDivID').innerHTML
    });
    console.log(p);
}
phantom.exit();
});