ctrl+鼠标左键监听

<!DOCTYPE html>
<html lang="en">
	<head>
		<meta charset="UTF-8">
		<title>div多选</title>
		<style>
			.container{
            width: 100px;
            height: 100px;
            background-color: #E6E6E6;
            border:1px solid #cccccc;
            text-align: center;
            line-height: 100px;
            float: left;
            margin-left: 20px;
        }
        .redBorder{
            border: 1px solid red;
        }
    </style>
		<script src="js/jquery-3.4.1.js" type="text/javascript"></script>
	</head>
	<body>
		<div class="box">
			<div class="container">DIV</div>
			<div class="container">DIV</div>
			<div class="container">DIV</div>
		</div>
	</body>
	<script>
		$(".container").mousedown(function(event) {
			if (event.button == 0) { // 鼠标左键
				if (event.ctrlKey) { //  ctrl
					if ($(this).hasClass("redBorder")) {
						$(this).removeClass("redBorder");
					} else {
						$(this).addClass("redBorder");
					}
				}
			}
		})
	</script>
</html>