CSS

change element in iframe

// so you got an iframe (id="myiframe"). In that page you have an element id="theprice" and you want to change its value
// from the parent page do this in your javascript:
var iframevar = document.getElementById('myiframe');
var elmnt = iframevar.contentWindow.document.getElementById("theprice");
elmnt.innerHTML = theNewPrice;

js change iframe content

$(iframeSelector).contents().find('html').html(htmlContent);

change iframe src

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js change iframe content

<iframe src="javascript:void(0);"></iframe>