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Generate pdf from html file without showing on browser

I want to generate a pdf file from html template which is not loaded in browser. The basic idea is to load html in some javascript variable and convert it to canvas/pdf without showing on browser.
Right now I am doing this by adding a frame on currently opened page and then removing frame after successfully generating it's pdf. But this is showing some fluctuation on the screen and scrollbar.
Current Code:
$http.get("static/templates/pdf-template.html")
.then(function (response) {
var html_string = response.data;
var iframe = document.createElement('iframe');
iframe.style.width = '100%';
document.body.appendChild(iframe);
setTimeout(function () {
var iframedoc = iframe.contentDocument || iframe.contentWindow.document;
iframedoc.body.innerHTML = html_string;
var divHeight = iframedoc.body.scrollHeight;
var divWidth = iframedoc.body.scrollWidth;
var ratio = divHeight / divWidth;
html2canvas(iframedoc.body, {
onrendered: function (canvas) {
var pdf = new jsPDF();
var width = pdf.internal.pageSize.width;
var height = pdf.internal.pageSize.height;
height = ratio * width;
var imgData = canvas.toDataURL('image/jpeg', 1.0);
pdf.addImage(imgData, 'JPEG', 0, 0, width, height);
pdf.save('pdf');
document.body.removeChild(iframe);
}
});
}, 10);
});
Please suggest solution without using iframe.

I face this issue just now. I didn't any proper way. Even though I get a solution maybe, it will work. you just make your non-wanted portion of html style z-index: -1; and wanted portion of html style z-index: 1;

Screen Resizing Javascript

function sizeChange() {
var container = document.getElementById('container');
var main = document.getElementById('main');
var content = document.getElementById('content');
var h = window.innerHeight;
container.style.height = h;
main.style.height = h*.9;
content.style.height = (h*.9)*.9;
}
document.addEventListener("resize", sizeChange);
I'm trying to manipulate the items in my html so the height of the container is constantly the height of the window and that when it's scaled, the height of the container scales. I have it set up so it gets the ID of each element it's going to manipulate and then adjusts by a % of what I want it to be. Does anyone have any feedback on why this is happening?

I would think most of what you are doing could be done with CSS. If you want to stick with JS, then you need to add units to your values. So change the code to something like
container.style.height = h+"px";
main.style.height = Math.floor(h*.9)+"px";
content.style.height = Math.floor((h*.9)*.9)+"px";

Resize image before loading - jquery

I'm using this plugin to create image zoom and gallery, yet I want to scale all images to fit with the container (using ratio algorithm).
Here is ratio function :
function scaleSize(maxW, maxH, currW, currH){
var ratio = currH / currW;
if(currW >= maxW && ratio <= 1){
currW = maxW;
currH = currW * ratio;
} else if(currH >= maxH){
currH = maxH;
currW = currH / ratio;
}
return [currW, currH];
}
And this is how the gallery load images :
var img = $('<img>').load(function(){
img.appendTo(a);
image_container.html(a);
}).attr('src', src).addClass(opts.big_image_class);
What I've tried :
var newSize = scaleSize(300, 320, $(".simpleLens-big-image").width(), $(".simpleLens-big-image").height());
var img = $('<img>').load(function(){
img.appendTo(a);
image_container.html(a);
}).attr('src', src).addClass(opts.big_image_class).width(newSize[0]).height(newSize[1]);
But scaleSize is not working properly since the current width and height is not yet defined (image not yet exist in dom).
Thanks for any pointers.

I took a look into plugin code and think you call your scaleSize() too early. An image with class simpleLens-big-image exists first after var img is set up and addClass() is done.
Try following:
var img = $('<img>').load(function(){
img.appendTo(a);
image_container.html(a);
}).attr('src', src).addClass(opts.big_image_class);
// at this point img should contain $(".simpleLens-big-image") so we can refer to img
var newSize = scaleSize(300, 320, img[0].naturalWidth, img[0].naturalHeight());
img.width(newSize[0]).height(newSize[1]);

Try something like this and call the onload method. This will make sure that the image is loaded to the DOM before you resize
var img = $('<img>');
img.src = src ;
img.onload = function() {
// Run onload code.
} ;

how to resize div when browser resize using javascript

Is it possible to resize the entire 'div' container using javascript ? Inside my div i have 2 images and placed one over another. 1st image has is 720x1280 and 2nd image has 40x40. Now, while resizing my div container both the images should get resized proposinally.
function addWidth() {
var elem = document.getElementById("Image1");
if (elem != null) {
var mydiv = elem.clientWidth;
document.getElementById("divImage").style.width = mydiv + "px";
}
}
function resizediv() {
var height = window.innerWidth;
if (document.body.clientHeight) {
height = document.body.clientHeight;
}
height = parseInt(height) - 10;
document.getElementById("Image1").style.height = parseInt(height - document.getElementById("divImage").offsetTop - 8) + "px";
}
window.onresize = resizediv;
I have tried for an single image and its works fine. But i want the same to happens for an div container.

Try this:
$(window).resize(function() {
addWidth();
resizediv();
});
Along with this, like #Alex said, you can also add width:100% for the images.

IE 6,7,8 don't support onload event in image object or DOM

My application has a large size of images to present and which should be resized for uniformly presentation with fixed width and height, to do so I write a JavaScript method in image's onload image like this:
var autoResizeImage = function(targetWidth, targetHeight, objImg) {
if (0 >= targetWidth || 0 >= targetHeight) {
// Ilegal parameters, just return.
return;
}
var img = new Image();
img.src = objImg.src;
// Calculate the width and height immediately the image is loaded.
img.onload = function() {
var hRatio;
var wRatio;
var width = img.width;
var height = img.height;
var calcWidth = width;
var calcHeight = height;
wRatio = targetWidth / width;
hRatio = targetHeight / height;
if (wRatio < hRatio) {
calcHeight = targetHeight;
calcWidth = (targetHeight / height) * width;
} else {
calcWidth = targetWidth;
calcHeight = (targetWidth / width) * height;
}
objImg.width = calcWidth;
objImg.height = calcHeight;
};
};
HTML image:
<img src='PATH' onload='autoResizeImage(100, 100, this)'>
This way works well on Chrome and Firefox except IE 6,7,8. I'm suffering on this, how can I complete this task on IE 6,7,8.
Thanks so much.

I would start by saying that if you're serving images to be displayed at a particular size, you should send them from the server at the correct size in the first place. Sending excessively large images and having the browser resize them is poor practice because it means that you're using up a lot more bandwidth than you need to. Your users may have restricted bandwidth, and may not appreciate the extra load time on your page caused by this.
However, I don't really know why you need to do this resizing exersise at all? HTML will by default scale an image to the size of the <img> tag that contains it anyway, so all you need to do is specify height and width styles for your <img> tag, and the scaling will be done automatically. There should be absolutely no need for all that messing around with Javascript.
<img src='PATH' style='width:100px; height:100px;'>
That should work in all browsers; no JS required. The image should be scaled for you.
But ideally, as I said, please try to avoid sending excessively large images to the page if you're not going to use them at full size.

Change the order of assignments. First assign onload function and then src attribute. It works for IE 8 at least.
var div = document.getElementById('div');
var img = new Image();
img.onload = function() {
var text = document.createTextNode('loaded ' + img.src);
div.appendChild(text);
};
window.setTimeout(function() {
var random = Math.random();
img.src ="http://stackoverflow.com/users/flair/450989.png?random=" + random;
}, 1000);
div.appendChild(img);
<div id="div"/>