truncateString.js 1.0 KB

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  1. /**
  2. * Truncates a string to the given number of chars (maxLength) by inserting '...' in the middle of that string.
  3. * Partially taken from https://stackoverflow.com/a/5723274/3192470.
  4. *
  5. * @param {string} string - string to be truncated
  6. * @param {number} maxLength - maximum size of the resulting string
  7. * @returns {string}
  8. */
  9. const separator = '...'
  10. export default function truncateString (string, maxLength) {
  11. // Return the empty string if maxLength is zero
  12. if (maxLength === 0) return ''
  13. // Return original string if it's already shorter than maxLength
  14. if (string.length <= maxLength) return string
  15. // Return truncated substring appended of the ellipsis char if string can't be meaningfully truncated
  16. if (maxLength <= separator.length + 1) return `${string.slice(0, maxLength - 1)}…`
  17. const charsToShow = maxLength - separator.length
  18. const frontChars = Math.ceil(charsToShow / 2)
  19. const backChars = Math.floor(charsToShow / 2)
  20. return string.slice(0, frontChars) + separator + string.slice(-backChars)
  21. }