Promise和async\await

回调函数

用来处理异步问题，例如发送Ajax，setTimeout等

Promise

    new Promise((resolve, reject) => {
        let resolves = "success";
        let errors = "error";
        function success() {
            setTimeout(function () {
                resolve(resolves);//then 的回调
            }, 1500)
        }
        success();
    }).then((res) => {
        console.log(res); //success
    }).catch((error) => {
        console.log(error);
    })

封装的例子

小程序
小程序

async\await

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