isBase64.js 880 B

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  1. import assertString from './util/assertString';
  2. import merge from './util/merge';
  3. var base64WithPadding = /^[A-Za-z0-9+/]+={0,2}$/;
  4. var base64WithoutPadding = /^[A-Za-z0-9+/]+$/;
  5. var base64UrlWithPadding = /^[A-Za-z0-9_-]+={0,2}$/;
  6. var base64UrlWithoutPadding = /^[A-Za-z0-9_-]+$/;
  7. export default function isBase64(str, options) {
  8. var _options;
  9. assertString(str);
  10. options = merge(options, {
  11. urlSafe: false,
  12. padding: !((_options = options) !== null && _options !== void 0 && _options.urlSafe)
  13. });
  14. if (str === '') return true;
  15. if (options.padding && str.length % 4 !== 0) return false;
  16. var regex;
  17. if (options.urlSafe) {
  18. regex = options.padding ? base64UrlWithPadding : base64UrlWithoutPadding;
  19. } else {
  20. regex = options.padding ? base64WithPadding : base64WithoutPadding;
  21. }
  22. return (!options.padding || str.length % 4 === 0) && regex.test(str);
  23. }