i have the index.html page.
Inside that page i have javascript code that makes a button to evoke ajax request for the other.html to be shown inside a div in index.html .
The other.html have nothing else but a div ( that contains the content ) and some javascript code.
The other.html loads normally inside the index.html but the javascript code does not work.
Anyone know why is this happening?
Thank you.
( the javascript code is as simple as an alert("hello") message ).
code:
index.html:
<html>
<head>
<script src=main.js></script>
</head>
<body>
<div id="to_change">bla bla bla</div>
<div id="button">click me</div>
</body>
<html>
main.js:
...
...
function sendRequest()
{
request.open("GET","other.html",true);
request.onreadystatechange = function(){
if(request.readyState == 4 && request.status == 200){
var response = request.responseText;
if(response) {
document.getElementById("to_change").innerHTML = response;
}
}
}
request.send(null);
}
....button.click(...sendRequest...);
...
...
other.html
<script type=...>alert("hello");</script>
<div>text text text text</div>
javascript is loading but function call is not happening.
You are not calling the functions in any event.
<BODY onLoad="alert('hello world!')">
Like this try to call the function . On any event you want
Make sure to remove the enclosing '<doctype...>', '<html>', and '<body>' tags from the "other.html" file, in case they are present.
You could try running the scripts manually:
// ...
if (response) {
var toChange=document.getElementById("to_change"), scripts, i;
toChange.innerHTML = response;
scripts = toChange.getElementsByTagName('script');
for (i=0; i<scripts.length; i++) {
eval(scripts[i].innerHTML);
}
}
Of course, eval is evil, so use at your own risk...
Related
I want home.html to load in <div id="content">.
<div id="topBar"> HOME </div>
<div id ="content"> </div>
<script>
function load_home(){
document.getElementById("content").innerHTML='<object type="type/html" data="home.html" ></object>';
}
</script>
This works fine when I use Firefox. When I use Google Chrome, it asks for plug-in. How do I get it working in Google Chrome?
I finally found the answer to my problem. The solution is
function load_home() {
document.getElementById("content").innerHTML='<object type="text/html" data="home.html" ></object>';
}
Fetch API
function load_home (e) {
(e || window.event).preventDefault();
fetch("http://www.yoursite.com/home.html" /*, options */)
.then((response) => response.text())
.then((html) => {
document.getElementById("content").innerHTML = html;
})
.catch((error) => {
console.warn(error);
});
}
XHR API
function load_home (e) {
(e || window.event).preventDefault();
var con = document.getElementById('content')
, xhr = new XMLHttpRequest();
xhr.onreadystatechange = function (e) {
if (xhr.readyState == 4 && xhr.status == 200) {
con.innerHTML = xhr.responseText;
}
}
xhr.open("GET", "http://www.yoursite.com/home.html", true);
xhr.setRequestHeader('Content-type', 'text/html');
xhr.send();
}
based on your constraints you should use ajax and make sure that your javascript is loaded before the markup that calls the load_home() function
Reference - davidwalsh
MDN - Using Fetch
JSFIDDLE demo
You can use the jQuery load function:
<div id="topBar">
HOME
</div>
<div id ="content">
</div>
<script>
$(document).ready( function() {
$("#load_home").on("click", function() {
$("#content").load("content.html");
});
});
</script>
Sorry. Edited for the on click instead of on load.
Fetching HTML the modern Javascript way
This approach makes use of modern Javascript features like async/await and the fetch API. It downloads HTML as text and then feeds it to the innerHTML of your container element.
/**
* #param {String} url - address for the HTML to fetch
* #return {String} the resulting HTML string fragment
*/
async function fetchHtmlAsText(url) {
return await (await fetch(url)).text();
}
// this is your `load_home() function`
async function loadHome() {
const contentDiv = document.getElementById("content");
contentDiv.innerHTML = await fetchHtmlAsText("home.html");
}
The await (await fetch(url)).text() may seem a bit tricky, but it's easy to explain. It has two asynchronous steps and you could rewrite that function like this:
async function fetchHtmlAsText(url) {
const response = await fetch(url);
return await response.text();
}
See the fetch API documentation for more details.
I saw this and thought it looked quite nice so I ran some tests on it.
It may seem like a clean approach, but in terms of performance it is lagging by 50% compared by the time it took to load a page with jQuery load function or using the vanilla javascript approach of XMLHttpRequest which were roughly similar to each other.
I imagine this is because under the hood it gets the page in the exact same fashion but it also has to deal with constructing a whole new HTMLElement object as well.
In summary I suggest using jQuery. The syntax is about as easy to use as it can be and it has a nicely structured call back for you to use. It is also relatively fast. The vanilla approach may be faster by an unnoticeable few milliseconds, but the syntax is confusing. I would only use this in an environment where I didn't have access to jQuery.
Here is the code I used to test - it is fairly rudimentary but the times came back very consistent across multiple tries so I would say precise to around +- 5ms in each case. Tests were run in Chrome from my own home server:
<!DOCTYPE html>
<html>
<head>
<script src="https://code.jquery.com/jquery-2.1.4.min.js"></script>
</head>
<body>
<div id="content"></div>
<script>
/**
* Test harness to find out the best method for dynamically loading a
* html page into your app.
*/
var test_times = {};
var test_page = 'testpage.htm';
var content_div = document.getElementById('content');
// TEST 1 = use jQuery to load in testpage.htm and time it.
/*
function test_()
{
var start = new Date().getTime();
$(content_div).load(test_page, function() {
alert(new Date().getTime() - start);
});
}
// 1044
*/
// TEST 2 = use <object> to load in testpage.htm and time it.
/*
function test_()
{
start = new Date().getTime();
content_div.innerHTML = '<object type="text/html" data="' + test_page +
'" onload="alert(new Date().getTime() - start)"></object>'
}
//1579
*/
// TEST 3 = use httpObject to load in testpage.htm and time it.
function test_()
{
var xmlHttp = new XMLHttpRequest();
xmlHttp.onreadystatechange = function() {
if (xmlHttp.readyState == 4 && xmlHttp.status == 200)
{
content_div.innerHTML = xmlHttp.responseText;
alert(new Date().getTime() - start);
}
};
start = new Date().getTime();
xmlHttp.open("GET", test_page, true); // true for asynchronous
xmlHttp.send(null);
// 1039
}
// Main - run tests
test_();
</script>
</body>
</html>
try
async function load_home(){
content.innerHTML = await (await fetch('home.html')).text();
}
async function load_home() {
let url = 'https://kamil-kielczewski.github.io/fractals/mandelbulb.html'
content.innerHTML = await (await fetch(url)).text();
}
<div id="topBar"> HOME </div>
<div id="content"> </div>
When using
$("#content").load("content.html");
Then remember that you can not "debug" in chrome locally, because XMLHttpRequest cannot load -- This does NOT mean that it does not work, it just means that you need to test your code on same domain aka. your server
You can use the jQuery :
$("#topBar").on("click",function(){
$("#content").load("content.html");
});
$("button").click(function() {
$("#target_div").load("requesting_page_url.html");
});
or
document.getElementById("target_div").innerHTML='<object type="text/html" data="requesting_page_url.html"></object>';
<script>
var insertHtml = function (selector, argHtml) {
$(document).ready(function(){
$(selector).load(argHtml);
});
var targetElem = document.querySelector(selector);
targetElem.innerHTML = html;
};
var sliderHtml="snippets/slider.html";//url of slider html
var items="snippets/menuItems.html";
insertHtml("#main",sliderHtml);
insertHtml("#main2",items);
</script>
this one worked for me when I tried to add a snippet of HTML to my main.html.
Please don't forget to add ajax in your code
pass class or id as a selector and the link to the HTML snippet as argHtml
There is this plugin on github that load content into an element. Here is the repo
https://github.com/abdi0987/ViaJS
load html form a remote page ( where we have CORS access )
parse the result-html for a specific portion of the page
insert that part of the page in a div on current-page
//load page via jquery-ajax
$.ajax({
url: "https://stackoverflow.com/questions/17636528/how-do-i-load-an-html-page-in-a-div-using-javascript",
context: document.body
}).done(function(data) {
//the previous request fails beceaus we dont have CORS on this url.... just for illlustration...
//get a list of DOM-Nodes
var dom_nodes = $($.parseHTML(data));
//find the question-header
var content = dom_nodes.find('#question-header');
//create a new div and set the question-header as it's content
var newEl = document.createElement("div");
$(newEl).html(content.html());
//on our page, insert it in div with id 'inserthere'
$("[id$='inserthere']").append(newEl);
});
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<p>part-result from other page:</p>
<div id="inserthere"></div>
Use this simple code
<div w3-include-HTML="content.html"></div>
<script>w3.includeHTML();</script>
</body>```
This is usually needed when you want to include header.php or whatever page.
In Javascript it's easy especially if you have HTML page and don't want to use php include function but at all you should write php function and add it as Javascript function in script tag.
In this case you should write it without function followed by name Just. Script rage the function word and start the include header.php
i.e convert the php include function to Javascript function in script tag and place all your content in that included file.
I use jquery, I found it easier
$(function() {
$("#navigation").load("navbar.html");
});
in a separate file and then load javascript file on html page
showhide.html
<!DOCTYPE html>
<html>
<head>
<script type="text/javascript">
function showHide(switchTextDiv, showHideDiv)
{
var std = document.getElementById(switchTextDiv);
var shd = document.getElementById(showHideDiv);
if (shd.style.display == "block")
{
shd.style.display = "none";
std.innerHTML = "<span style=\"display: block; background-color: yellow\">Show</span>";
}
else
{
if (shd.innerHTML.length <= 0)
{
shd.innerHTML = "<object width=\"100%\" height=\"100%\" type=\"text/html\" data=\"showhide_embedded.html\"></object>";
}
shd.style.display = "block";
std.innerHTML = "<span style=\"display: block; background-color: yellow\">Hide</span>";
}
}
</script>
</head>
<body>
<a id="switchTextDiv1" href="javascript:showHide('switchTextDiv1', 'showHideDiv1')">
<span style="display: block; background-color: yellow">Show</span>
</a>
<div id="showHideDiv1" style="display: none; width: 100%; height: 300px"></div>
</body>
</html>
showhide_embedded.html
<!DOCTYPE html>
<html>
<head>
<script type="text/javascript">
function load()
{
var ts = document.getElementById("theString");
ts.scrollIntoView(true);
}
</script>
</head>
<body onload="load()">
<pre>
some text 1
some text 2
some text 3
some text 4
some text 5
<span id="theString" style="background-color: yellow">some text 6 highlight</span>
some text 7
some text 8
some text 9
</pre>
</body>
</html>
If your html file resides locally then go for iframe instead of the tag. tags do not work cross-browser, and are mostly used for Flash
For ex : <iframe src="home.html" width="100" height="100"/>
I know this has been asked a lot on here, but all the answers work only with jQuery and I need a solution without it.
So after I do something, my Servlet leads me to a JSP page. My JS function should populate a drop down list when the page is loaded. It only works properly when the page is refreshed tho.
As I understand this is happening because I want to populate, using innerHTML and the JS function gets called faster then my HTML page.
I also get this error in my Browser:
Uncaught TypeError: Cannot read property 'innerHTML' of null
at XMLHttpRequest.xmlHttpRequest.onreadystatechange
I had a soulution for debugging but I can't leave it in there. What I did was, every time I opened that page I automatically refreshed the whole page. But my browser asked me every time if I wanted to do this. So that is not a solution that's pretty to say the least.
Is there something I could do to prevent this?
Edit:
document.addEventListener("DOMContentLoaded", pupulateDropDown);
function pupulateDropDown() {
var servletURL = "./KategorienHolen"
let xmlHttpRequest = new XMLHttpRequest();
xmlHttpRequest.onreadystatechange = function () {
if (xmlHttpRequest.readyState === 4 && xmlHttpRequest.status === 200) {
console.log(xmlHttpRequest.responseText);
let katGetter = JSON.parse(xmlHttpRequest.responseText);
JSON.stringify(katGetter);
var i;
for(i = 0; i <= katGetter.length -1; i++){
console.log(katGetter[i].id);
console.log(katGetter[i].kategorie);
console.log(katGetter[i].oberkategorie);
if (katGetter[i].oberkategorie === "B") {
document.getElementById("BKat").innerHTML += "" + katGetter[i].kategorie + "</br>";
} else if (katGetter[i].oberkategorie === "S") {
document.getElementById("SKat").innerHTML += "" + katGetter[i].kategorie + "</br>";
} else if (katGetter[i].oberkategorie ==="A") {
document.getElementById("ACat").innerHTML += "" + katGetter[i].kategorie + "</br>";
}
// document.getElementsByClassName("innerDiv").innerHTML = "" + katGetter.kategorie + "";
// document.getElementById("test123").innerHTML = "" + katGetter.kategorie + "";
}
}
};
xmlHttpRequest.open("GET", servletURL, true);
xmlHttpRequest.send();
}
It can depend on how + when you're executing the code.
<html>
<head>
<title>In Head Not Working</title>
<!-- WILL NOT WORK -->
<!--<script>
const p = document.querySelector('p');
p.innerHTML = 'Replaced!';
</script>-->
</head>
<body>
<p>Replace This</p>
<!-- Will work because the page has finished loading and this is the last thing to load on the page so it can find other elements -->
<script>
const p = document.querySelector('p');
p.innerHTML = 'Replaced!';
</script>
</body>
</html>
Additionally you could add an Event handler so when the window is fully loaded, you can then find the DOM element.
<html>
<head>
<title>In Head Working</title>
<script>
window.addEventListener('load', function () {
const p = document.querySelector('p');
p.innerHTML = 'Replaced!';
});
</script>
</head>
<body>
<p>Replace This</p>
</body>
</html>
Define your function and add an onload event to body:
<body onload="pupulateDropDown()">
<!-- ... -->
</body>
Script needs to be loaded again, I tried many options but <iframe/> works better in my case. You may try to npm import for library related to your script or you can use the following code.
<iframe
srcDoc={`
<!doctype html>
<html>
<head>
<style>[Style (If you want to)]</style>
</head>
<body>
<div>
[Your data]
<script type="text/javascript" src="[Script source]"></script>
</div>
</body>
</html>
`}
/>
Inside srcDoc, it's similar to normal HTML code.
You can load data by using ${[Your Data]} inside srcDoc.
It should work :
document.addEventListener("DOMContentLoaded", function(){
//....
});
You should be using the DOMContentLoaded event to run your code only when the document has been completely loaded and all elements have been parsed.
window.addEventListener("DOMContentLoaded", function(){
//your code here
});
Alternatively, place your script tag right before the ending body tag.
<body>
<!--body content...-->
<script>
//your code here
</script>
</body>
While converting a script to not require jQuery, I've discovered that if I load my content (a partial html page with html and javascript) via XMLHttpRequest, the javascript in the partial page does not work. But if I load the partial using jQuery.load, it does work.
I've tried digging through jQuery's load function to see if it's doing anything special and nothing jumped out at me. I've been banging my head against the wall and searching for an answer for a couple of days now to no avail.
What am I doing wrong/how can I make it work like it does when loaded with jQuery.load?
EDIT
I got the XMLHttpRequest method to work by splitting out out my javascript from the html in the fragment and loading the javascript using the suggested technique here: https://stackoverflow.com/a/11695198/362958. However, that still does not provide an explanation of why jQuery.load works. Is jQuery umtimately parsing the HTML and doing the same thing for any scripts it finds within the content it loads?
I've set up a plunker (https://plnkr.co/edit/wE9RuULx251C5ARnUbCh) with the following code that demonstrates the issue. Note: once you load the fragment with jQuery, it will continue to work and you'll have to restart the plunk for the XMLHttpRequest method to fail again.
index.html:
<!DOCTYPE html>
<html>
<head>
<script data-require="jquery#*" data-semver="3.0.0" src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.0.0/jquery.js"></script>
<link rel="stylesheet" href="style.css" />
<script src="script.js"></script>
</head>
<body>
<h3>Buttons</h3>
<div>
<input type="button" value="Load with XMLHttpRequest" onclick="loadXMLDoc('ajaxContentDiv', 'fragmentToLoad.html');"> (Links do not work if loaded this way... Script from fragmentToLoad.html not loaded in DOM?) <br/><br/>
<input type="button" value="Load with JQuery" onclick="jQuery('#ajaxContentDiv').load('fragmentToLoad.html');"> (Links will work if loaded this way)
</div>
<br/>
<br/>
<br/>
<div id="ajaxContentDiv">Content will load here...</div>
</body>
</html>
script.js:
function loadXMLDoc(targetDivName, url) {
var xmlhttp = new XMLHttpRequest();
xmlhttp.open("GET", url, true);
xmlhttp.onreadystatechange = function () {
if (xmlhttp.readyState == XMLHttpRequest.DONE) {
if (xmlhttp.status == 200) {
document.getElementById(targetDivName).innerHTML = xmlhttp.responseText;
}
}
};
xmlhttp.send();
}
fragmentToLoad.html:
<div id="divToBeUpdated">
<span id="stringBox">String here</span>
</div>
<br/>
<h3>Links</h3>
<div>
Link 1<br>
Link 2<br>
Link 3<br>
</div>
<script>
function updateDiv(string){
var stringBox = document.getElementById('stringBox');
stringBox.innerHTML = string;
}
</script>
You can use single .html file, and you are on the correct track by splitting the html content - though you can also split the html content of a single file, rather than requesting two files. #Barmar explains the functionality of jQuery's .load() method at this comment.
script.js
function loadXMLDoc(targetDivName, url) {
var xmlhttp = new XMLHttpRequest();
xmlhttp.open("GET", url, true);
xmlhttp.onreadystatechange = function() {
if (xmlhttp.readyState == XMLHttpRequest.DONE) {
if (xmlhttp.status == 200) {
// create a `div` elemenent, append response to `div` element
// get specific elements by `id`, append `script` element to `document.body`
var content = document.createElement("div");
content.innerHTML = xmlhttp.responseText
var div = content.querySelector("#htmlContent");
var contentScript = content.querySelector("#contentScript");
var script = document.createElement("script");
script.textContent = contentScript.textContent;
document.getElementById(targetDivName).innerHTML = div.innerHTML;
document.body.appendChild(script);
}
}
};
xmlhttp.send();
}
fragmentToLoad.html
<div id="htmlContent">
<div id="divToBeUpdated">
<span id="stringBox">String here</span>
</div>
<br/>
<h3>Links</h3>
<div class="links">
Link 1
<br>
Link 2
<br>
Link 3
<br>
</div>
</div>
<script type="text/javascript" id="contentScript">
function updateDiv(string) {
var stringBox = document.getElementById('stringBox');
stringBox.innerHTML = string;
}
// attach `click` event to `.link a` elements here
var links = document.querySelectorAll(".links a");
for (var i = 0; i < links.length; i++) {
(function(link, i) {
console.log(i)
link.addEventListener("click", function(e) {
e.preventDefault();
updateDiv("Hello World " + i)
})
})(links[i], i)
}
</script>
plnkr https://plnkr.co/edit/7fLtGRSV7WlH2enLbwSW?p=preview
I'm using QUnit for unit testing js and jquery.
My HTML looks like this:
<!DOCTYPE html>
<html>
<head>
<title>QUnit Test Suite</title>
<script src="../lib/jquery.js"></script>
<link rel="stylesheet" href="http://code.jquery.com/qunit/qunit-1.16.0.css" type="text/css" media="screen">
<script type="text/javascript" src="http://code.jquery.com/qunit/qunit-1.16.0.js"></script>
<!--This is where I may have to add startPage.html--->
<script src="../login.js"></script>
<script src="../test/myTests.js"></script>
</head>
<body>
<div id="qunit"></div>
<div id="qunit-fixture"></div>
</body>
</html>
Currently, I'm adding login.js as shown and I'm getting references correctly to objects defined in login.js.
However, functions in login.js contains references to some dom elements defined in startPage.html which is located elsewhere.
So, if I say $('#login-btn'), it is throwing an error. Is there any way to fix this?
Can I
(a) refer to startPage.html to my qunit page given above?
(b) refer to or load startPage.html in the file where I'm running tests (myTests.js):
QUnit.test( "a test", function( assert ) {
assert.equal( 1, "1", "String '1' and number 1 have the same value" );//works
assert.equal( login.abc, "abc", "Abc" );//works with attributes
assert.equal(($("#userid").val()),'', 'Userid field is present');//fails
assert.equal( login.ValidUserId(), true, "ValidUserId" );//fails with functions
});
Does QUnit provide any method to load Html/php files so they'll be defined prior to testing. Like 'fixtures' in jasmine?
EDIT: Please also tell what to do in case I have startPage.php
There are a couple of ways you can do this. The simplest is just to use the built-in QUnit "fixtures" element. In your QUnit HTML file, simply add any HTML you want in the div with the id of qunit-fixture. Any HTML you put in there will be reset to what it was on load before each test (automatically).
<html>
...
<body>
<div id='qunit'></div>
<div id='qunit-fixture'>
<!-- everything in here is reset before each test -->
<form>
<input id='userid' type='text'>
<input id='login-btn' type='submit'>
</form>
</div>
</body>
</html>
Note that the HTML in the fixture doesn't really have to match what you have in production, but obviously you can do that. Really, you should just be adding the minimal necessary HTML so that you can minimize any side effects on your tests.
The second option is to actually pull in the HTML from that login page and delay the start of the QUnit tests until the HTML loading is complete:
<html>
<head>
...
<script type="text/javascript" src="http://code.jquery.com/qunit/qunit-1.16.0.js"></script>
<script>
// tell QUnit you're not ready to start right away...
QUnit.config.autostart = false;
$.ajax({
url: '/path/to/startPage.html',
dataType: 'html',
success: function(html) {
// find specific elements you want...
var elem = $(html).find(...);
$('#qunit-fixture').append(elem);
QUnit.start(); // ...tell QUnit you're ready to go
}
});
</script>
...
</head>
...
</html>
Another way to do this without using jquery is as follows
QUnit.config.autostart = false;
window.onload = function() {
var xhr = new XMLHttpRequest();
if (xhr) {
xhr.onloadend = function () {
if(xhr.status == 200) {
var txt = xhr.responseText;
var start = txt.indexOf('<body>')+6;
var end = txt.indexOf('</body>');;
var body_text = txt.substring(start, end);
var qunit_fixture_body = document.getElementById('qunit-fixture');
qunit_fixture_body.innerHTML = body_text;
}
QUnit.start();
}
xhr.open("GET", "index.html");
xhr.send();
} else {
QUnit.start(); //If getting the html file from server fails run tests and fail anyway
}
}
Is there a solution to get the "foo bar" in JS (with jQuery ?) in this code ?
<!DOCTYPE html>
<html>
<body role="application" onload="foo bar">
<div>...</div>
</body>
</html>
I'am using PhantomJS in my script.
EDIT: "foo bar" is an example. It's juste the value I would get.
EDIT 2: my code (wich don't work) is http://paste.awesom.eu/nca&ln.
EDIT 3: PROBLEM(S) AND SOLUTION
After many hours I find many problems and solutions.
First, the website is only accesible in https and I can't include jQuery file from non https url. That's why I have include the jQuery file from the website.
I have debug this with this code :
page.onConsoleMessage = function(msg) {
console.log(msg);
};
Then, I need to change my user agent because the website has a whitelist.
page.settings.userAgent = 'Mozilla/5.0 (X11; Linux x86_64; rv:25.0) Gecko/20100101 Firefox/25.0';
Finaly the code is:
page.open(url, function(status) {
if ( status === "success" ) {
page.includeJs(url_js_file, function() {
page.evaluate(function() {
console.log("> " + $("body").attr("onload"));
});
phantom.exit();
});
}
});
Thank you for comments and anwers.
It looks like you are not returning your variable out of evaluate.
To do that you must
var bodyonload = page.evaluate(function (s) {
return document.body.getAttribute('onload');
}, 'bodyonload');
You were very close to having it.
Here is your code where it returns an object rather than just a variable. I figured it could be useful.
page.open(url, function (status) {
if (status !== 'success') {
console.log('FAILED: ' + status);
} else {
var result = page.evaluate(function (s) {
var result = {
bodyOnLoad: document.body.getAttribute('onload'),
documentTitle: document.title
};
return result;
}, 'result');
console.log(result.bodyOnLoad);
}
phantom.exit();
});
Hope that helps
Edit:
Looked at it some more and perhaps there is a problem with your reference to jquery in page.injectJs(), is jquery in the same directory?
There should be no space between function name, It should like <body role="application" onload="foobar()"> instead of <body role="application" onload="foo bar">
In between HTML head tag,
<script>
function foobar(){
alert('Am loaded');
}
</script>
Try:
document.body.getAttribute("onload")
If you want to get the actual, literal value of onload, use $('body').attr('onload'). This will return the value of any attribute, for any element (assuming jQuery is being used). If not using jQuery, document.body.getAttribute("onload") should do the trick.
Keep in mind that since PhantomJS technically runs outside of the targeted page's DOM, you need to wrap any DOM scripts in page.evaluate:
page.evaluate(function () {
// put your $('body').attr('onload') bit here.
});
This worked for me for returning the value in onload.
<!DOCTYPE html>
<html>
<body role="application" onload="foo bar">
<div>...</div>
<script src="http://code.jquery.com/jquery.js"></script>
<script>
console.log($("body").attr("onload"));
</script>
</body>
</html>