The concat() method concatenates given arguments to the given string.
Example
let emptyString = "";
// joint arguments string
let joinedString = emptyString.concat("JavaScript", " is", " fun.");
console.log(joinedString);
// Output: JavaScript is fun.
concat() Syntax
The syntax of the concat() method is:
str.concat(str1, ..., strN)
Here, str is a string.
concat() Parameters
The concat() method takes in an arbitrary number of strings to concatenate to str.
concat() Return Value
- Returns a new string containing the combined text of the strings provided.
Note: The assignment operators like + and += are strongly recommended over the concat() method.
Example: Using concat() method
console.log("".concat({})); // [object Object]
console.log("".concat(null)); // null
console.log("".concat(true)); // true
console.log("".concat(4, 5)); // 45
let str1 = "Hello";
let str2 = "World";
// concatenating two strings
let newStr = str1.concat(", ", str2, "!");
console.log(newStr); // Hello, World!
Output
[object Object] null true 45 Hello, World!
Recommended Reading: JavaScript Array concat()