PHP functions can return multiple types of values: no return value, primitive type, array, object, resource. Using type hints (such as : int) to specify the return value type ensures that the function returns the expected type, improving code reliability and maintainability.
The type of value returned by PHP function
PHP function can return different types of values, including:
- No return value (void)
- Primitive type(int, float, string, bool)
- Array
- Object
- Resource
To specify the return value type of a function, use the following before the function name One of type hints:
int
float
string
bool
array
object
resource
Practical case
The following function gets the number of lines of the specified file and returns an integer:
function get_line_count(string $filename): int { $file = fopen($filename, 'r'); $lines = 0; while (!feof($file)) { fgets($file); $lines++; } fclose($file); return $lines; }
This function uses : int
type hint, indicating that it will return an integer. The code then uses fopen()
to open the file and read it line by line, while incrementing the $lines
count. Finally, it returns the value of $lines
.
Using type hints can help ensure that functions return values of the expected type, thereby improving the reliability and maintainability of your code.
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