# 2022.05.19

### 字节

```js
Promise.all((Promise.then(1), 2).then(v=> console.log(v))) // 输出1,2

Promise.all((Promise.then(1), 2, Promise.reject(3)).then(v=> console.log(v))) // 3

Promise.all((setTimeout()=>{console.log(1), 500}, 2, Promise.reject(3)).then(v=> console.log(v))) // 1,2,3


```

Promise.all 的规则是这样的

```js
Promise.all = function (arr) {
  let index = 0,
    result = [];
  return new Promise((resolve, reject) => {
    arr.forEach((p, i) => {
      Promise.resolve(p).then(
        (val) => {
          index++;
          result[i] = val;
          if (index === arr.length) {
            resolve(result);
          }
        },
        (err) => {
          reject(err);
        }
      );
    });
  });
};
```

### 数字证书是个啥玩意

[HTTP 详解.md](/blog/html-and-css/http-xiang-jie.md)

### 为什么非对称加密比对称加密慢？

[常见加密算法浅析](/blog/za-wen/chang-jian-jia-mi-suan-fa-qian-xi.md)

### https 运用了那种加密

[HTTP 详解.md](/blog/html-and-css/http-xiang-jie.md)


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