13 lines
411 B
JavaScript
13 lines
411 B
JavaScript
import assertString from './util/assertString';
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var notBase64 = /[^A-Z0-9+\/=]/i;
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export default function isBase64(str) {
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assertString(str);
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var len = str.length;
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if (!len || len % 4 !== 0 || notBase64.test(str)) {
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return false;
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}
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var firstPaddingChar = str.indexOf('=');
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return firstPaddingChar === -1 || firstPaddingChar === len - 1 || firstPaddingChar === len - 2 && str[len - 1] === '=';
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} |