FileSize.js

  1. /**
  2.  * Creates a new FileSize
  3.  *
  4.  * @param {number} bytes Number of bytes
  5.  * @constructor
  6.  */
  7. function FileSize(bytes) {
  9.   /**
  10.    * Number of bytes
  11.    * @type {number}
  12.    */
  13.   this.bytes = bytes;
  16.   /**
  17.    * Returns this.bytes as human-readable file size string
  18.    *
  19.    * @returns {string} Human-readable file size string
  20.    */
  21.   this.toReadableString = function() {
  22.     return FileSize.getReadableString(this.bytes);
  23.   };
  25. }
  27. /**
  28.  * List of available size units
  29.  *
  30.  * @constant
  31.  * @type {string[]}
  32.  */
  33. FileSize.UNITS = ['B', 'KB', 'MB', 'GB', 'TB', 'EB', 'ZB', 'YB'];
  35. /**
  36.  * 1B in bytes
  37.  *
  38.  * @constant
  39.  * @type {number}
  40.  */
  41. FileSize.B = 1;
  43. /**
  44.  * 1KB in bytes
  45.  *
  46.  * @constant
  47.  * @type {number}
  48.  */
  49. FileSize.KB = 1024 * FileSize.B;
  51. /**
  52.  * 1MB in bytes
  53.  *
  54.  * @constant
  55.  * @type {number}
  56.  */
  57. FileSize.MB = 1024 * FileSize.KB;
  59. /**
  60.  * 1GB in bytes
  61.  *
  62.  * @constant
  63.  * @type {number}
  64.  */
  65. FileSize.GB = 1024 * FileSize.MB;
  67. /**
  68.  * 1TB in bytes
  69.  *
  70.  * @constant
  71.  * @type {number}
  72.  */
  73. FileSize.TB = 1024 * FileSize.GB;
  75. /**
  76.  * 1EB in bytes
  77.  *
  78.  * @constant
  79.  * @type {number}
  80.  */
  81. FileSize.EB = 1024 * FileSize.TB;
  83. /**
  84.  * Returns human-readable file size string from given number of bytes
  85.  *
  86.  * @param {number} bytes Number of bytes
  87.  * @returns {string} Human-readable file size string
  88.  */
  89. FileSize.getReadableString = function(bytes) {
  90.   let i;
  91.   let val = bytes;
  93.   for (i = 0; i < FileSize.UNITS.length; i++) {
  94.     if(val < 1000) break;
  95.     val /= 1024;
  96.   }
  98.   return (i === 0 ? val : val.toFixed(1)) + FileSize.UNITS[i];
  99. };
  102. export default FileSize;