split and join
- Dart course
- Beginner
- Lesson 88/116
- 5 min
Learn string splitting with split and join.
split and join
In Dart you split a string with split. You pass a delimiter; the string is divided on it and a List<String> is returned. For example "a,b,c".split(",") gives you ["a", "b", "c"].
To do the reverse, that is to combine a list into a single string, use join. ["a", "b"].join("-") returns "a-b". Together they are very handy for parsing CSV lines, log entries or user input.
Choosing a delimiter
The delimiter does not have to be a single character. A multi-character delimiter works too: "a::b::c".split("::") is valid. Likewise join accepts a long separator; ["a", "b"].join(" - ") places - between each element.
An empty delimiter "".split("") breaks the string into individual characters. This is a convenient way to walk a string as a list of characters. If the list is empty, join still returns an empty string, so an empty check is usually not needed.
Practice Your turn: split and join
Split the string "apple,pear,banana" on the comma and join it back with " - ". Print the result with print.
Starter code
void main() {
// Split "apple,pear,banana" on the comma
// Join with " - " and print
}Sample solution
void main() {
final fruit = "apple,pear,banana";
final parts = fruit.split(",");
print(parts.join(" - "));
}Expected output
apple - pear - banana
Questions and answers
Review the lesson questions together with their answers. To test yourself, solve the lesson interactively.
1 Which method divides a string into parts?
final part = "a,b,c"._____(",");- split Correct answer
- join
- trim
- replaceAll
Explanation: split divides the string on the given delimiter.
2 The split call
final parts = "apple,pear,banana".____(",");final parts = "apple,pear,banana".split(",");Explanation: split(",") breaks the string on commas.
3 Match split and join
| Term | Meaning |
|---|---|
split |
divides a string |
join |
combines a list |
"," (delimiter) |
splits on commas |
List<String> |
split's return type |