记录一些 Node.js 中的流格式转换代码。

## Base64 转 Buffer

```js
const buffer = Buffer.from(base64Str, 'base64');
```

## Buffer 转 Base64

```js
const base64Str = buffer.toString(‘base64’)
```

## Buffer 转 Blob

需传文件 MIME 格式

```js
const blob = new Blob([dataBuffer], { type: mime });
```

## Blob 转 Buffer

先获取 arrayBuffer 后转换

```js
const buffer = Buffer.from(await blob.arrayBuffer());
```


Node.js 中 Blob、Buffer、Base64 相互转换

<p>记录一些 Node.js 中的流格式转换代码。</p>
<h2>Base64 转 Buffer</h2>
<pre><code class="language-js">const <span class="hljs-built_in">buffer</span> = <span class="hljs-built_in">Buffer</span>.from(base64Str, <span class="hljs-string">&#x27;base64&#x27;</span>);
</code></pre>
<h2>Buffer 转 Base64</h2>
<pre><code class="language-js">const base64Str = buffer.<span class="hljs-keyword">to</span><span class="hljs-constructor">String(‘<span class="hljs-params">base64</span>’)</span>
</code></pre>
<h2>Buffer 转 Blob</h2>
<p>需传文件 MIME 格式</p>
<pre><code class="language-js">const blob = <span class="hljs-keyword">new</span> <span class="hljs-constructor">Blob([<span class="hljs-params">dataBuffer</span>], { <span class="hljs-params">type</span>: <span class="hljs-params">mime</span> })</span>;
</code></pre>
<h2>Blob 转 Buffer</h2>
<p>先获取 arrayBuffer 后转换</p>
<pre><code class="language-js"><span class="hljs-keyword">const</span> buffer = Buffer.<span class="hljs-keyword">from</span>(await blob.<span class="hljs-built_in">array</span>Buffer());
</code></pre>
