js节流快速记忆核心记忆点：在判断flag的if下设置flag=false。

核心记忆点：在判断flag的if下设置flag=false。

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
<body>
    <button id="btn">提交</button>
    <script>
        var oBtn = document.getElementById("btn");
        oBtn.onclick = throttle();
        function show() {
            setTimeout(function(){
                console.log("模拟的ajax执行了！");
            },3000)
        }
        function throttle(){
            var flag = true;
            return function(){
                if(!flag) return ;
                flag = false;
                timer = setTimeout(function(){
                    show();
                    flag = true;
                },500)
            }     
        }

    </script>
</body>
</html>