concatener javascript code example
Example 1: js concat string
const str1 = 'Hello';
const str2 = 'World';
console.log(str1.concat(' ', str2));
// expected output: "Hello World"
console.log(str2.concat(', ', str1));
// expected output: "World, Hello"
Example 2: javascript concatenation
// the fastest way to string concat in cycle when number of string is less than 1e6
// see https://medium.com/@devchache/the-performance-of-javascript-string-concat-e52466ca2b3a
// see https://www.javaer101.com/en/article/2631962.html
function concat(arr) {
let str = '';
for (let i = 0; i < arr.length; i++) {
str += arr[i];
}
return str;
}