1.30 onclick指定的回调函数是异步执行的
<body>
<button onclick="print()">点击</button>
<script>
function print() {
console.log(1);
}
for (var i = 1; i <= 5000; i++) {
console.log(2);
}
</script>
</body>
<body>
<button onclick="print()">点击</button>
<script>
function print() {
console.log(1);
}
for (var i = 1; i <= 5000; i++) {
console.log(2);
}
</script>
</body>