ctype_xdigit
Description
The ctype_xdigit of Ctype for PHP checks for character(s) representing a hexadecimal digit.
Syntax
ctype_xdigit(
mixed $text
): boolParameters
text
The tested string.
NOTE: If an integer between -128 and 255 inclusive is provided, it is interpreted as the ASCII value of a single character (negative values have 256 added in order to allow characters in the Extended ASCII range). Any other integer is interpreted as a string containing the decimal digits of the integer.
Return
Returns true if every character in text is a hexadecimal 'digit', that is a decimal digit or a character from [A-Fa-f] , false otherwise.
When called with an empty string the result will always be false.
Examples
1 · text
<? $text = "0123456789ABCDEFabcdef"; $return = ctype_xdigit($text); var_export($return); ?>
true
2
<?
for($i = 0; $i <= 255; ++$i)
{
$return = ctype_xdigit($i);
if($return)
{
$character = chr($i);
echo "$i: $character\n";
}
}
?>48: 0 49: 1 50: 2 51: 3 52: 4 53: 5 54: 6 55: 7 56: 8 57: 9 65: A 66: B 67: C 68: D 69: E 70: F 97: a 98: b 99: c 100: d 101: e 102: f
