类：Hash

【Class: Hash】

• 继承: <stream.Transform>

Hash 类是一个用于创建数据哈希摘要的工具类。它可以用两种方式使用：

【The Hash class is a utility for creating hash digests of data. It can be used in one of two ways:】

• 作为一个既可读又可写的 溪流，数据写入后会在可读端生成计算出的哈希摘要，或
• 使用 hash.update() 和 hash.digest() 方法生成计算出的哈希。

crypto.createHash() 方法用于创建 Hash 实例。Hash 对象不应直接使用 new 关键字创建。

【The crypto.createHash() method is used to create Hash instances. Hash objects are not to be created directly using the new keyword.】

示例：将 Hash 对象用作流：

【Example: Using Hash objects as streams:】

const {
  createHash,
} = await import('node:crypto');

const hash = createHash('sha256');

hash.on('readable', () => {
  // Only one element is going to be produced by the
  // hash stream.
  const data = hash.read();
  if (data) {
    console.log(data.toString('hex'));
    // Prints:
    //   6a2da20943931e9834fc12cfe5bb47bbd9ae43489a30726962b576f4e3993e50
  }
});

hash.write('some data to hash');
hash.end();const {
  createHash,
} = require('node:crypto');

const hash = createHash('sha256');

hash.on('readable', () => {
  // Only one element is going to be produced by the
  // hash stream.
  const data = hash.read();
  if (data) {
    console.log(data.toString('hex'));
    // Prints:
    //   6a2da20943931e9834fc12cfe5bb47bbd9ae43489a30726962b576f4e3993e50
  }
});

hash.write('some data to hash');
hash.end();拷贝

示例：使用 Hash 和管道流：

【Example: Using Hash and piped streams:】

import { createReadStream } from 'node:fs';
import { stdout } from 'node:process';
const { createHash } = await import('node:crypto');

const hash = createHash('sha256');

const input = createReadStream('test.js');
input.pipe(hash).setEncoding('hex').pipe(stdout);const { createReadStream } = require('node:fs');
const { createHash } = require('node:crypto');
const { stdout } = require('node:process');

const hash = createHash('sha256');

const input = createReadStream('test.js');
input.pipe(hash).setEncoding('hex').pipe(stdout);拷贝

示例：使用 hash.update() 和 hash.digest() 方法：

【Example: Using the hash.update() and hash.digest() methods:】

const {
  createHash,
} = await import('node:crypto');

const hash = createHash('sha256');

hash.update('some data to hash');
console.log(hash.digest('hex'));
// Prints:
//   6a2da20943931e9834fc12cfe5bb47bbd9ae43489a30726962b576f4e3993e50const {
  createHash,
} = require('node:crypto');

const hash = createHash('sha256');

hash.update('some data to hash');
console.log(hash.digest('hex'));
// Prints:
//   6a2da20943931e9834fc12cfe5bb47bbd9ae43489a30726962b576f4e3993e50拷贝