(PHP 4 >= 4.0.4, PHP 5, PHP 7, PHP 8)
ctype_digit — Check for numeric character(s)
Checks if all of the characters in the provided string,
text, are numerical.
textThe tested string.
Note:
If an int 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.
Returns true if every character in the string
text is a decimal digit, false otherwise.
When called with an empty string the result will always be false.
Example #1 A ctype_digit() example
<?php
$strings = array('1820.20', '10002', 'wsl!12');
foreach ($strings as $testcase) {
if (ctype_digit($testcase)) {
echo "The string $testcase consists of all digits.\n";
} else {
echo "The string $testcase does not consist of all digits.\n";
}
}
?>The above example will output:
The string 1820.20 does not consist of all digits. The string 10002 consists of all digits. The string wsl!12 does not consist of all digits.
Example #2 A ctype_digit() example comparing strings with integers
<?php
$numeric_string = '42';
$integer = 42;
ctype_digit($numeric_string); // true
ctype_digit($integer); // false (ASCII 42 is the * character)
is_numeric($numeric_string); // true
is_numeric($integer); // true
?>