Description

The JavaScript method concat() concatenates the provided arguments to the string, in the same order.

  • Recommended to use the assignment operators + and += for string concatenation, as they are faster than the concat() method.

The below table summarizes its usage.

Usage Details
Syntax str.concat(str1, str2, ..., strN)
  • str is a string
  • str1, str2, and so on till strN are the string arguments
Parameters Takes an arbitrary number of strings to be concatenated with the string str.
Result Returns the concatenated string containing all the strings combined.
Category String Methods

Example: Using the method

For a valid integer index value, the method returns the character from the specified index.

var str1 = "Hello";
var str2 = "World";

// Concatenating the strings
var newStr = str1.concat(" ", str2, "!");
document.write(newStr);        // Prints: Hello World!

// Other examples
document.write("".concat(2, 3));              // Prints: 23
document.write("".concat(true, false));       // Prints: truefalse
document.write("".concat(null, null));        // Prints: nullnull
document.write("".concat({}, {}));            // Prints: [object object][object object]

Output:

Hello World!
23
truefalse
nullnull
[object object][object object]

Overall

The JavaScript method concat() returns the concatenated string character at a specified index in a string.

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