diff --git a/skills/javascript/async.drawio b/skills/javascript/async.drawio new file mode 100644 index 0000000..a2aacb7 --- /dev/null +++ b/skills/javascript/async.drawio @@ -0,0 +1,57 @@ + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + \ No newline at end of file diff --git a/skills/javascript/promise.js b/skills/javascript/promise.js new file mode 100644 index 0000000..63ccf68 --- /dev/null +++ b/skills/javascript/promise.js @@ -0,0 +1,69 @@ +function testApiCall(success, failed) { + var timeOut = Math.random() * 2; + console.log('set timeout to: ' + timeOut + ' seconds.'); + setTimeout(function () { + if (timeOut < 1) { + console.log('call resolve()...'); + success('200 OK'); + } + else { + console.log('call reject()...'); + failed('timeout in ' + timeOut + ' seconds.'); + } + }, timeOut * 1000); +} + +// 通过回调实现的异步方案 +// fna() +// fnb() +// fnc() +console.log('start ...') +testApiCall( + // success callback + (data) => { + console.log(data) + }, + // failed callback + (error) => { + console.log(error) + } +) +console.log('end ...') + +// fna(fnb_sucess(fnc_success(fnd_success)), fnb_error(fnc_error(fnd_error))) + +// promise 封装技术, 他让异步成为一种标准, 使用promise的标准方式来处理异常 +// promise 像一个接口，他约束了 excutor对象的 实现方式 +var p1 = new Promise(testApiCall) +// p1.then((data) => { +// console.log(data) +// // p2.then().catch().finally() +// }).catch((error) => { +// console.log(error) +// }).finally(() => { +// console.log('finnal') +// }) + + +// 异步等待 +// 一同步编程的方式，来实现异步代码 +var async_await = async () => { + try { + const resp = await p1 + console.log(resp) + + // const res2 = await p2 + // console.log(resp2) + + // const res3 = await p3 + // console.log(resp2) + } catch (error) { + console.log(error) + } +} + +async_await() + + + +