HTML2Canvas creating multiple divs - jspdf

Question

I'm trying to create a PDF using jsPDF and HTML2Canvas.
I have multiple DIVs to insert into the PDF.
If I try to put all DIVs into a container and render once then it only puts the first page height into the PDF.
Can't figure out how to render multiple divs and stick them in the same PDF so that it keeps going page by page.
JAVASCRIPT
function genPDF() {
html2canvas(document.getElementById("container"), {
onrendered: function (canvas) {
var img = canvas.toDataURL();
var doc = new jsPDF();
doc.addImage(img, 'PNG');
doc.addPage();
doc.save('test.pdf');
}
});
}
HTML
<div id="container">
<div class="divEl" id="div1">Hi <img src="img1.JPG"> </div>
<div class="divEl" id="div2">Why <img src="img2.PNG"> </div>
</div>
<button onClick="genPDF()"> Click Me </button>

Answer 1

Add each of your images separately.
You need to wait for all the html2canvas renderings are done and added to pdf and then save your final pdf.
One way to achieve this by using JQuery and array of promises, actual code would look like this:
function genPDF() {
var deferreds = [];
var doc = new jsPDF();
for (let i = 0; i < numberOfInnerDivs; i++) {
var deferred = $.Deferred();
deferreds.push(deferred.promise());
generateCanvas(i, doc, deferred);
}
$.when.apply($, deferreds).then(function () { // executes after adding all images
doc.save('test.pdf');
});
}
function generateCanvas(i, doc, deferred){
html2canvas(document.getElementById("div" + i), {
onrendered: function (canvas) {
var img = canvas.toDataURL();
doc.addImage(img, 'PNG');
doc.addPage();
deferred.resolve();
}
});
}

Answer 2

For me it works like that:
$('#cmd2').click(function () {
var len = 4; //$x(".//body/div/div").length
var pdf = new jsPDF('p', 'mm','a4');
var position = 0;
Hide
for (let i = 1;i <= len; i++){
html2canvas(document.querySelector('#pg'+i),
{dpi: 300, // Set to 300 DPI
scale: 1 // Adjusts your resolution
}).then(canvas => {
pdf.addImage(canvas.toDataURL("images/png", 1), 'PNG', 0,position, 210, 295);
if (i == len){
pdf.save('sample-file.pdf');
}else{
pdf.addPage();
}
});
}
});

Answer 3

You could try this, using the follwing javascript references in the HTML. Html2Canvas and jsPDF are quite picky with versions you use.
https://cdnjs.cloudflare.com/ajax/libs/html2canvas/0.4.1/html2canvas.js"
https://cdnjs.cloudflare.com/ajax/libs/jspdf/1.0.272/jspdf.debug.js"
var forPDF = document.querySelectorAll(".js-panel-pdf");
var len = forPDF.length;
var thisPDF = new jsPDF('p', 'mm', [240, 210]); //210mm wide and 297mm high
for (var i = 0; i < forPDF.length; i++) {
html2canvas(forPDF[i], {
onrendered: function(canvas) {
thisPDF.addImage(canvas.toDataURL("images/png", 1), 'PNG', 0, 0, 210, 295);
if (parseInt(i + 1) === len) {
thisPDF.save('sample-file.pdf');
} else {
thisPDF.addPage();
}
}
});
}

Answer 4

Stuart Smith - This is not working it does not allow to download the pdf
here is java script code
function generatePDF(){
var imgData;
var forPDF = document.querySelectorAll(".summary");
var len `enter code here`= forPDF.length;
var doc =new jsPDF('p','pt','a4');
for (var i = 0; i < forPDF.length; i++){
html2canvas(forPDF[i],{
useCORS:true,
onrendered:function(canvas){
imgData = canvas.toDataURL('image/jpg',1.0);
var doc =new jsPDF('p','pt','a4');
doc.addImage(imgData,'jpg',10,10,500,480);
if (parseInt(i + 1) === len) {
doc.save('sample-file.pdf');
} else {
doc.addPage();
}
}
});
}
}