Example code
- Dart course
- Intermediate
- Lesson 110/116
- 5 min
Learn example code in documentation.
Example code
Example code in doc comments shows the reader how to use the API. A Markdown code block starts with ```dart and ends with ```.
Each line must start with ///; so you write /// ```dart and add lines like /// square(4); below it.
dartdoc renders the code block as syntax-highlighted HTML; this clearly explains how to use the API.
An example code example
Typical usage: under /// Example: you write /// ```dart, then /// final sum = add(2, 3); and finally /// ```.
The code block should contain real working code; comments are added with //. dartdoc highlights it as-is.
Pick short, meaningful examples; long ones bloat the docs and reduce readability.
Practice A doc comment with example code
Write int square(int n) => n * n;. Add a doc comment above it: first line /// Example:, second line /// ```dart, third line /// square(4); // 16, fourth line /// ```. In main call print(square(5)).
Starter code
// Write the square function and its example code block
void main() {
// print the result of square(5)
}Sample solution
/// Example:
/// ```dart
/// square(4); // 16
/// ```
int square(int n) => n * n;
void main() {
print(square(5));
}Expected output
25
Questions and answers
Review the lesson questions together with their answers. To test yourself, solve the lesson interactively.
1 Code block start
/// ____dart/// ```dartExplanation: ```dart starts a code block.
2 Example code parts
| Term | Meaning |
|---|---|
```dart |
Code block |
/// |
Doc comment |
// 16 |
Inline comment |
Example: |
Label |
3 How does an example code block start?
- ```dart Correct answer
- <code>
- [code]
- //code
Explanation: ```dart opens a Markdown code block.