StringUtils

Overview

Tools to convert strings into bytes and vice-versa.

The RxPlayer internally has a lot of code dealing with strings to bytes conversion (and vice-versa). This tool exports that logic so you don’t have to rewrite it yourself.

You might need one of those functions for example when dealing with challenge and licenses, which are often under a binary format.

How to import it

The simplest way to import the StringUtils is by importing it as a named export from “rx-player/tools”, like so:

import { StringUtils } from "rx-player/tools";

console.log(StringUtils.strToUtf8("hello😀"));

You can also import only the function(s) you want to use by importing it directly from “rx-player/tools/string-utils”:

import { strToUtf8 } from "rx-player/tools/string-utils";
console.log(strToUtf8("hello😀"));

StringUtils functions

StringUtils is an object containing the following functions:

• strToUtf8: Convert a JS string passed as argument to an Uint8Array of its corresponding representation in UTF-8.

  Example:

  import { StringUtils } from "rx-player/tools";
  StringUtils.strToUtf8("hello😀");
  // => Uint8Array(9) [ 104, 101, 108, 108, 111, 240, 159, 152, 128 ]
  //                    "h"  "e"  "l"  "l"  "o"  "grinning face" emoji
  

• utf8ToStr: Convert a Uint8Array containing a string encoded with UTF-8 into a JS string.

  Example:

  import { StringUtils } from "rx-player/tools";
  const uint8Arr = new Uint8Array([
    104,
    101,
    108,
    108,
    111,
    240,
    159,
    152,
    128,
  ]);
  StringUtils.utf8ToStr(uint8Arr);
  // => "hello😀"
  

  Note: if what you have is an ArrayBuffer, you have to convert it to an Uint8Array first:

  import { StringUtils } from "rx-player/tools";
  const toUint8Array = new Uint8Array(myArrayBuffer);
  console.log(StringUtils.utf8ToStr(toUint8Array));
  

• strToUtf16LE: Convert a JS string passed as argument to an Uint8Array containing its corresponding representation in UTF-16-LE (little endian UTF-16).

  Example:

  import { StringUtils } from "rx-player/tools";
  StringUtils.strToUtf16LE("hi😀");
  // => Uint8Array(9) [ 104, 0, 105, 0, 61, 216, 0, 222 ]
  //                    "h"     "i"     "grinning face" emoji
  

• utf16LEToStr: Convert a Uint8Array containing a string encoded with UTF-16-LE (little endian UTF-16) into a JS string.

  Example:

  import { StringUtils } from "rx-player/tools";
  const uint8Arr = new Uint8Array([104, 0, 105, 0, 61, 216, 0, 222]);
  StringUtils.utf16LEToStr(uint8Arr);
  // => "hi😀"
  

  Note: if what you have is an ArrayBuffer, you have to convert it to an Uint8Array first:

  import { StringUtils } from "rx-player/tools";
  const toUint8Array = new Uint8Array(myArrayBuffer);
  console.log(StringUtils.utf16LEToStr(toUint8Array));
  

• strToUtf16BE: Convert a JS string passed as argument to an Uint8Array containing its corresponding representation in UTF-16-BE (big endian UTF-16).

  Example:

  import { StringUtils } from "rx-player/tools";
  StringUtils.strToUtf16BE("hi😀");
  // => Uint8Array(9) [ 0, 104, 0, 105, 216, 61, 222, 0 ]
  //                    "h"     "i"     "grinning face" emoji
  

• utf16BEToStr: Convert a Uint8Array containing a string encoded with UTF-16-BE (big endian UTF-16) into a JS string.

  Example:

  import { StringUtils } from "rx-player/tools";
  const uint8Arr = new Uint8Array([0, 104, 0, 105, 216, 61, 222, 0]);
  StringUtils.utf16BEToStr(uint8Arr);
  // => "hi😀"
  

  Note: if what you have is an ArrayBuffer, you have to convert it to an Uint8Array first:

  import { StringUtils } from "rx-player/tools";
  const toUint8Array = new Uint8Array(myArrayBuffer);
  console.log(StringUtils.utf16BEToStr(toUint8Array));