问题
When I view the page source of a page (like this for example: http://my.sa.ucsb.edu/public/curriculum/coursesearch.aspx) there's not very much code/info in it. On that linked page, for instance, none of the class info is shown in the page source.
BUT: when I view it in firebug, I can see a lot more of the html information. For instance, I can see all of the class info, in tables.
Why is this? How can I access the full (firebug html)? Can I do it in php/javascript?
回答1:
This is the order in which stuff happens:
- PHP generates HTML
- Browser loads HTML
- JavaScript manipulate loaded HTML
Why is this?
The view source browser feature normally shows the plain HTML as received by the browser. Other advanced tools like Firefug are able to display the current HTML after being changed by JavaScript. (Firefox itself has this feature as well: just right click on some generated HTML and choose "View selected source".)
How can I access the full (firebug html)?
I'm not sure about the HTML tab but the Network tab always displays documents as received from the server.
Can I do it in php/javascript?
PHP is no longer running when the original HTML reaches the browser.
JavaScript can display HTML with the .innerHTML property of any DOM node.
回答2:
View Source shows what the browser got from the server. Firebug shows the browser DOM - i.e. representation of the page view that exists in browser memory. DOM can be changed by Javascript. Javascript can access DOM by using document value and then going to its children, etc. - for example, to see all tables, you might do document.getElementsByTagName('table')
If you want whole DOM contents as HTML, you can do something like document.getElementsByTagName('html')[0].innerHTML
回答3:
View Source simply shows you the HTML loaded from the server, which means that any changes done to the DOM after the page has been loaded will not be shown. The Page source only shows you the first source when the page finishes loading.
On the other hand, Firebug is dynamic and shows you the DOM and how it is being manipulated. When the DOM is being changed, Firebug's source will change as well. This is important for debugging as you can see what is really going on, unlike the View Source.
回答4:
When viewing the source with "View Source", the HTML you view is the HTML of the URL you are in, and the HTML without any modification from JavaScript and the sort. Also, if the page had frames or iframes in its code, the content of them will not show either.
Instead, in firebug, changes to HTML dynamically and content of frames/iframes will be visible.
Also, viewing the source of a page before it's fully loaded, can be a reason of not having the whole HTML code (or any HTML code at all).
Traversing the HTML code with JavaScript will always return the full updated HTML code. (i.e. what you would see in firebug)
I'm not sure how you want to access the HTML with PHP, but PHP does not have access to the code after it reaches the browser. But if you are sending a URL to PHP to load the HTML, the HTML you will have is the original HTML before any dynamic changes (i.e. the one you would see in "View Source")
回答5:
Also firebug will show you the css file which will just be targeted from the main html via
<link rel="stylesheet" type="text/css" href="css">
Therefore showing some more information.
回答6:
Page source shows you HTML when page was loaded for first time. It does not show you modifications made using javascript etc after page was loaded or after you clicked any button on webpage. To view the currently visible DOM, you can use the following:
For IE/firefox, following bookmarklet works: https://www.squarefree.com/bookmarklets/webdevel.html#generated_source
For google chrome, right click on any element and choose 'Inspect Element' option. It will show the position of element in DOM. Now right click on '
For opera, right click on any element and choose 'Inspect element'. This will start opera dragonfly. In dragonfly window, Click on 'Expand the DOM tree' button (first button with a dot and two arrows) and then 'export the current DOM panel' button (second button)
In IE, open the webpage and press F12 to open developer tools. Click View->Source->DOM(page) or shortcut Ctrl+Shift+G in developer tools window. This will show the complete currently visible DOM.
For firefox, alternative is Web developer toolbar extension and choose View Source->View Generated source in it.
回答7:
View source gives you the source of the page when it is loaded, to get the current html, there is a option in web developer tool (Firefox addon) - "View generated source"
in menu :
view source -> view generated source
来源：https://stackoverflow.com/questions/4396462/differences-view-page-source-vs-view-in-firebug