静态方法：Buffer.concat(list[, totalLength])

🌐 Static method: Buffer.concat(list[, totalLength])

• list <Buffer[]> | <Uint8Array[]> 需要连接的 Buffer 或 Uint8Array 实例列表。
• totalLength <integer> 当连接时，list 中 Buffer 实例的总长度。
• 返回：<Buffer>

返回一个新的 Buffer，它是将 list 中的所有 Buffer 实例连接在一起的结果。

🌐 Returns a new Buffer which is the result of concatenating all the Buffer instances in the list together.

如果列表没有项目，或者 totalLength 为 0，则会返回一个新的零长度 Buffer。

🌐 If the list has no items, or if the totalLength is 0, then a new zero-length Buffer is returned.

如果未提供 totalLength，则通过将 list 中 Buffer 实例的长度相加来计算。

🌐 If totalLength is not provided, it is calculated from the Buffer instances in list by adding their lengths.

如果提供了 totalLength，它会被强制转换为无符号整数。如果 list 中 Buffer 的总长度超过 totalLength，结果会被截断到 totalLength。

🌐 If totalLength is provided, it is coerced to an unsigned integer. If the combined length of the Buffers in list exceeds totalLength, the result is truncated to totalLength.

import { Buffer } from 'node:buffer';

// Create a single `Buffer` from a list of three `Buffer` instances.

const buf1 = Buffer.alloc(10);
const buf2 = Buffer.alloc(14);
const buf3 = Buffer.alloc(18);
const totalLength = buf1.length + buf2.length + buf3.length;

console.log(totalLength);
// Prints: 42

const bufA = Buffer.concat([buf1, buf2, buf3], totalLength);

console.log(bufA);
// Prints: <Buffer 00 00 00 00 ...>
console.log(bufA.length);
// Prints: 42const { Buffer } = require('node:buffer');

// Create a single `Buffer` from a list of three `Buffer` instances.

const buf1 = Buffer.alloc(10);
const buf2 = Buffer.alloc(14);
const buf3 = Buffer.alloc(18);
const totalLength = buf1.length + buf2.length + buf3.length;

console.log(totalLength);
// Prints: 42

const bufA = Buffer.concat([buf1, buf2, buf3], totalLength);

console.log(bufA);
// Prints: <Buffer 00 00 00 00 ...>
console.log(bufA.length);
// Prints: 42拷贝

Buffer.concat() 也可能像 Buffer.allocUnsafe() 一样使用内部 Buffer 池。