代码示例:(标识:eg_js_array_push_length)
<!DOCTYPE html>
<html>
<body>

<h1>JavaScript 数组方法</h1> 

<h2>push()</h2>

<p>push() 方法返回新的数组长度。</p>

<button onclick="myFunction()">试一试</button>

<p id="demo1"></p>
<p id="demo2"></p>

<script>
var fruits = ["Banana", "Orange", "Apple", "Mango"];
document.getElementById("demo1").innerHTML = fruits;

function myFunction() {
  document.getElementById("demo2").innerHTML = fruits.push("Lemon");
  document.getElementById("demo1").innerHTML = fruits;
}
</script>

</body>
</html>
运行结果: