[HTML/CSS/JS] Base64编码

• 将二进制数据拆分成6比特的小块。
• 将每个6比特的块转换为对应的Base64字符。
• 将所有的Base64字符组合成一个字符串。
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复制代码
let binaryData = 'Hello World!'.split('').map(c => c.charCodeAt(0)); // 将字符串转换为二进制数据

let base64Chars = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/';

let base64Data = '';
let remainder = 0;
let remainderSize = 0;
for (let i = 0; i < binaryData.length; i++) {
  let byte = binaryData[i];
  let char1 = base64Chars[(byte >> 2) & 0x3f];
  let char2 = base64Chars[((byte << 4) + remainder) & 0x3f];
  base64Data += char1 + char2;
  remainder = (byte << 2) & 0x3f;
  remainderSize += 2;
  if (remainderSize == 6) {
    base64Data += base64Chars[remainder];
    remainder = 0;
    remainderSize = 0;
  }
}
if (remainderSize > 0) {
  base64Data += base64Chars[remainder];
  base64Data += '=';
  if (remainderSize == 2) {
    base64Data += '=';
  }
}

console.log(base64Data); // 输出 "SGVsbG8gV29ybGQh"

复制代码
import { Base64 } from 'js-base64';

let binaryData = 'Hello World!'.split('').map(c => c.charCodeAt(0)); // 将字符串转换为二进制数据

let base64Data = Base64.encode(binaryData);

console.log(base64Data); // 输出 "SGVsbG8gV29ybGQh"