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How to perform PHP parameter type hinting? 1. Use a colon after the parameter name to specify the type; 2. PHP provides built-in types such as int, float, string, etc.; 3. Using type hints can improve code readability, improve performance, and enable IDE functions; 4. Ensure that the function only receives the correct type to prevent unexpected errors.
#How to set type hints in PHP function parameters?
Type hints are a feature in PHP that allow you to specify the data type of function parameters. This provides the following benefits:
Set type hints
To set type hints for a parameter of a PHP function, follow the parameter name with a colon (:) and then specify the type. Here are some examples:
function sum(int $a, int $b): int { return $a + $b; } function greet(string $name): void { echo "Hello, $name!"; } function divide(float $a, float $b): float { return $a / $b; }
Built-in types
PHP provides the following built-in types:
int
- Integerfloat
- Floating point numberstring
- Stringnull
- Null valuevoid
- Indicates that the function does not return any value array
- Array bool
- Boolean value callable
- Callable itemiterable
- Iterable itemPractical case
Let us consider an example where we use type hints for a function that calculates the sum of two numbers:
function sum(int $a, int $b): int { return $a + $b; } // 正确的用法 $result = sum(1, 2); // 抛出 TypeError 异常 sum("1", "2"); // 字符串参数,需要整数
By using type hints, we ensure that sum()
The function only accepts integer arguments, preventing unexpected type mismatch errors.
Note:
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