[Web] 取消Promise

转载自 为Promise插上可取消的翅膀

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const makeCancelable = (promise) => {   let hasCanceled_ = false;   const wrappedPromise = new Promise((resolve, reject) => {     promise.then((val) =>       hasCanceled_ ? reject({isCanceled: true}) : resolve(val)     );     promise.catch((error) =>       hasCanceled_ ? reject({isCanceled: true}) : reject(error)     );   });   return {     promise: wrappedPromise,     cancel() {       hasCanceled_ = true;     },   }; };

　　

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//调用 const somePromise = new Promise(r => setTimeout(r, 1000));//创建一个异步操作 const cancelable = makeCancelable(somePromise);//为异步操作添加可取消的功能 cancelable   .promise   .then(() => console.log('resolved'))   .catch(({isCanceled, ...error}) => console.log('isCanceled', isCanceled)); // 取消异步操作 cancelable.cancel();