47 lines
1.3 KiB
Markdown
47 lines
1.3 KiB
Markdown
---
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title: Promise Resolve
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localeTitle: 承诺解决
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---
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## 承诺解决
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### 描述
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`Promise.resolve`函数表示Promise的成功完成。此函数允许您将Promise返回给调用函数。
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`Promise.resolve`接受一个参数返回调用函数。此参数可以是值，也可以是其他Promise。
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resolve函数的“值”可以是基本的JavaScript类型，数组或对象。
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```javascript
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Promise.resolve('success'); // string
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Promise.resolve([2, 3, 5]); // array
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Promise.resolve({name: 'John', age: '43'}); // object
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```
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“thenable”是一个将两个回调函数作为参数的函数。您可以使用第一个参数触发成功完成，第二个参数返回Promise上的错误。
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```javascript
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thenableFunction = {then: function(onSuccesss, onFailure) {
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if (condition === 'success') {
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onSuccess(paramList); // success condition
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} else {
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onFailure(paramList); // error condition
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}
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}
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}
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Promise.resolve(thenableFunction);
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```
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将then函数链接到promise调用者将使您可以访问`Promise.resolve`的结果。
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```javascript
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promiseCallingFunction(paramList)
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.then(function(value) {
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/*
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* this is where you get access to the value
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* returned by a promise on successful completion
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*/
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});
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``` |