Joining Array Elements with join
The join method in JavaScript is a powerful tool for converting arrays into strings. It works by concatenating all the elements of an array, inserting a specified separator between each element. This is especially useful when you need to present array data in a human-readable format, such as displaying a list of items separated by commas, spaces, or custom characters. Using join can help you create neatly formatted output for user interfaces, logs, or data exports.
12345const words = ["JavaScript", "arrays", "are", "powerful"]; console.log(words.join(" ")); // JavaScript arrays are powerful console.log(words.join(", ")); // JavaScript, arrays, are, powerful console.log(words.join(" - ")); // JavaScript - arrays - are - powerful console.log(words.join("")); // JavaScriptarraysarepowerful
Note
There is a key difference between the
joinandtoStringmethods for arrays. While both convert arrays to strings,joinlets you specify a custom separator, buttoStringalways uses a comma. This makesjoinmuch more flexible for formatting array output exactly as you need.
1. What will be the result of the following code?
2. Fill in the blank to join the array elements with a slash ("/") so that the output is "2024/6/10".
Obrigado pelo seu feedback!
Pergunte à IA
Pergunte à IA
Pergunte o que quiser ou experimente uma das perguntas sugeridas para iniciar nosso bate-papo
Can you explain more about how the `join` method works with different data types in an array?
What happens if I use `join` on an empty array?
Can you show an example comparing `join` and `toString` with the same array?
Awesome!
Completion rate improved to 8.33Joining Array Elements with join
Deslize para mostrar o menu
The join method in JavaScript is a powerful tool for converting arrays into strings. It works by concatenating all the elements of an array, inserting a specified separator between each element. This is especially useful when you need to present array data in a human-readable format, such as displaying a list of items separated by commas, spaces, or custom characters. Using join can help you create neatly formatted output for user interfaces, logs, or data exports.
12345const words = ["JavaScript", "arrays", "are", "powerful"]; console.log(words.join(" ")); // JavaScript arrays are powerful console.log(words.join(", ")); // JavaScript, arrays, are, powerful console.log(words.join(" - ")); // JavaScript - arrays - are - powerful console.log(words.join("")); // JavaScriptarraysarepowerful
Note
There is a key difference between the
joinandtoStringmethods for arrays. While both convert arrays to strings,joinlets you specify a custom separator, buttoStringalways uses a comma. This makesjoinmuch more flexible for formatting array output exactly as you need.
1. What will be the result of the following code?
2. Fill in the blank to join the array elements with a slash ("/") so that the output is "2024/6/10".
Obrigado pelo seu feedback!
