How to Convert an Array to a String Without Commas in JavaScript

To convert an array to a string without commas in JavaScript, call the join() method on the array, passing an empty string ('') as an argument:

const arr = ['coffee', 'milk', 'tea'];

const withoutCommas = arr.join('');
console.log(withoutCommas); // coffeemilktea

The Array join() method returns a string containing each array element concatenated with the specified separator. If no separator is passed as an argument, it will join the array elements with commas:

const arr = ['coffee', 'milk', 'tea'];

const str = arr.join();
console.log(str); // coffee,milk,tea

We can specify other separators apart from an empty string, like hyphens and slashes:

const arr = ['coffee', 'milk', 'tea'];

const withHypens = arr.join('-');
console.log(withHypens); // coffee-milk-tea

const withSlashes = arr.join('/');
console.log(withSlashes); // coffee/milk/tea

const withSpaces = arr.join(' ');
console.log(withSpaces); // coffee milk tea

A separator can also contain multiple characters:

const arr = ['coffee', 'milk', 'tea'];

const withAnd = arr.join(' and ');
console.log(withAnd); // coffee and milk and tea

const withOr = arr.join(' or ');
console.log(withOr); // coffee or milk or tea

If an element in the array is undefined, null, or an empty array ([]), it will be converted to an empty string ('') before concatenation with the separator. For example:

const arr = ['coffee', null, 'milk', []];

const withComma = arr.join(',');
console.log(withComma); // coffee,,milk,

const withHyphen = arr.join('-');
console.log(withHyphen); // coffee--milk-

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