[JavaScript] テキストエリアの高さを自動調節するやつ

jquery.textareaAutoHeigh.js

(function($){
	var update = function(obj, min){
		var br = obj.val().match(/(\r\n|\n)/gm);
		if (br) {
			if (br.length >= min) {
				obj.prop('rows', br.length + 1);
			}
		} else {
			obj.prop('rows', min);
		}
	};

	this.each(function(){
		var t = $(this),
		min = Number(t.prop('rows') || 1);
		t.data('ah-minrow', min);

		if (this.value) {
			update(t, min);
		}

		t.on('keyup change cut paste', function(e){
			var code = (e.keyCode || e.which), type = e.type;
			if (13 === code || 8 === code || 46 === code || (e.ctrlKey && 90 === code)) {
				update(t, min);
			} else if ('paste' === type || 'cut' === type) {
				var th = $(this);
				setTimeout(function() {
					update(th, th.data('ah-minrow'));
				}, 100);
			}
		});
	});
})(jQuery);