Joining strings except empty ones in javascript-CodePudding

I was wondering what is the best way to join a few strings in javascript except if they are empty.

Say we have

let s1 = 'X = 1';
let s2 = '';
let s3 = 'Z = 3';

And my end result need to be "X = 1, Z = 3"

let str = [s1,s2,s3].join(',')  // will have extra comma

let str = [s1!??' , ' ,s2!??' , ' ,s3].join(' ')  //is ugly, and will not work

let str = [u1&&',' ,u2&&',',u3].join('')  //close, but no cigar.

But I am sure there must be an elegant way to do this join!

And someone here on stackoverflow will point me in the right direction.

CodePudding user response：

You can use .filter(Boolean) (which is the same as .filter(x => x)) removes all falsy values (null, undefined, empty strings etc...)

Working Demo :

let s1 = 'X = 1';
let s2 = '';
let s3 = 'Z = 3';

let str = [s1,s2,s3].filter(Boolean).join(", ");

console.log(str);

CodePudding user response：

let str = [u1,u2,u3].filter(Boolean).join(',');