Here is a function to print a PDF from an iframe.
You just need to pass the URL of the PDF to the function. It will create an iframe and trigger print once the PDF is load.
Note that the function doesn't destroy the iframe. Instead, it reuses it each time the function is call. It's hard to destroy the iframe because it is needed until the printing is done, and the print method doesn't has callback support (as far as I know).
printPdf = function (url) {
var iframe = this._printIframe;
if (!this._printIframe) {
iframe = this._printIframe = document.createElement('iframe');
document.body.appendChild(iframe);
iframe.style.display = 'none';
iframe.onload = function() {
setTimeout(function() {
iframe.focus();
iframe.contentWindow.print();
}, 1);
};
}
iframe.src = url;
}