User:Awesome Aasim/copycodeblock.js

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This user script seems to have a documentation page at User:Awesome Aasim/copycodeblock.

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$(document).ready(function() {
	$('.mw-highlight').prepend($('<a href="javascript:void(0)">Copy code</a>').click(function(e) {
		e.preventDefault();
		var value = $(this).parent().find('pre').text();
		var $temp = $("<textarea>");
		$("body").append($temp);
		$temp.val(value).select();
		document.execCommand("copy");
		$temp.remove();
		$(this).text("Copied!");
		var that = this;
		window.setTimeout(function() {
			$(that).text("Copy code");
		}, 3000);
	}))
});