(PHP 8 >= 8.6.0)
clamp — Return the given value if in range, else return the nearest bound
Return the given value if in range of min and max.
Else if it's lower than min, return min.
Else return max.
注意:
Values of different types will be compared using the standard comparison rules. For instance, a non-numeric string will be compared to an int as though it were
0, but multiple non-numeric string values will be compared alphanumerically. The actual value returned will be of the original type with no conversion applied.
Be careful when passing arguments of different types because clamp() can produce unpredictable results.
value
Any comparable
value to be clamped between min and max.
min
A comparable minimum to limit
the value to.
max
A comparable maximum to limit
the value to.
clamp() returns the parameter value if
considered "between" min and max according to standard
comparisons.
If min is greater than max,
clamp() throws a ValueError.
If min or max is NAN,
clamp() throws a ValueError.
<?php
echo clamp(-5, min: 0, max: 100), PHP_EOL; // 0
echo clamp(55, min: 0, max: 100), PHP_EOL; // 55
echo clamp(103, min: 0, max: 100), PHP_EOL; // 100
echo clamp("J", min: "A", max: "F"), PHP_EOL; // "F"
clamp(
new \DateTimeImmutable('2025-08-01'),
min: new \DateTimeImmutable('2025-08-15'),
max: new \DateTimeImmutable('2025-09-15'),
)->format('Y-m-d'), PHP_EOL; // 2025-08-15
?>