w3resource

JavaScript: encodeURIComponent functions

Description

The encodeURIComponent function is used to encodes a Uniform Resource Identifier (URI) component by replacing each instance of certain characters by one, two or three escape sequences representing the UTF-8 encoding of the character.

encodeURIComponent escapes all characters except the following:
alphabetic, decimal digits, - _ . ! ~ * ' ( )

Syntax

encodeURIComponent(str1)

Parameters

str1: A complete, encoded Uniform Resource Identifier.

Example encodeURIComponent Functions

In the following web document encodeURIComponent() function is used to encode a URL parameter.

JavaScript Code:

xyz = encodeURIComponent("http://myw3r.com/x=31&y=21");
//Lets create an URL
url1 = "https://w3resource.com/xyz=" + xyz + "&xyz3=45";
//Here is the complete URL
console.log(url1);

View the example in the browser

Live demo

See the Pen encodeURIComponent-function-1 by w3resource (@w3resource) on CodePen.


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JavaScript: Tips of the Day

Returns all unique values of an array, based on a provided comparator function

Example:

const tips_uniqueElementsBy = (arr, fn) =>
  arr.reduce((acc, v) => {
    if (!acc.some(x => fn(v, x))) acc.push(v);
    return acc;
  }, []);

console.log(tips_uniqueElementsBy(
  [
    { id: 0, value: 'p' },
    { id: 1, value: 'q' },
    { id: 2, value: 'r' },
    { id: 1, value: 's' },
    { id: 0, value: 't' }
  ],
  (a, b) => a.id == b.id
));

Output:

[[object Object] {
  id: 0,
  value: "p"
}, [object Object] {
  id: 1,
  value: "q"
}, [object Object] {
  id: 2,
  value: "r"
}]