The Uint8Array array represents an array of 8-bit unsigned integers. By default, the contents of Uint8Array are initialized to 0.
The Uint8Array.from() method is used to create a new Uint8Array from an array-like or iterable object. So when you want to convert an arrayLike or iterable object then you can be used this function by passing the object as a parameter to this function along with map function and value used for map function if needed.
Syntax:
Uint8Array.from( source, mapFn, thisArg )
parameters: This method accept three parameters as mentioned above and described below:
- source: This parameter contains an array-like or iterable object which is used to convert to a Uint8Array object.
- mapFn: It is an optional parameter which is Map function to call on every element of the Uint8Array array.
- thisArg: It is an optional parameter which store the value to use as this when executing mapFn.
Return Value: This method returns a new Uint8Array instance.
Below example illustrate the working of Uint8Array.from() method in JavaScript:
Program 1:
<script> // Create a Uint8Array from a string like structure var array = Uint8Array.from( '45465768654323456' ); // Print the result document.write(array); </script> |
4, 5, 4, 6, 5, 7, 6, 8, 6, 5, 4, 3, 2, 3, 4, 5, 6
Program 2:
<script> // Create a Uint8Array from a array by adding // 3 to each number using function var array = Uint8Array.from([1, 2, 3, 4, 5, 6], z => z+3); // Print the result document.write(array); </script> |
4, 5, 6, 7, 8, 9
References: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray/from