Returns true if bytes are in the range of \x00-\x1f or \x7f (del). Returns false if bytes are in the range of \x20-\x7e or \x80-\xff.
(PHP 4 >= 4.0.4, PHP 5, PHP 7, PHP 8)
ctype_cntrl — Check for control character(s)
Checks if all of the characters in the provided string,
text, are control characters.
Control characters are e.g. line feed, tab, escape.
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 text is
a control character from the current locale, false otherwise.
When called with an empty string the result will always be false.
Example #1 A ctype_cntrl() example
<?php
$strings = array('string1' => "\n\r\t", 'string2' => 'arf12');
foreach ($strings as $name => $testcase) {
if (ctype_cntrl($testcase)) {
echo "The string '$name' consists of all control characters.\n";
} else {
echo "The string '$name' does not consist of all control characters.\n";
}
}
?>The above example will output:
The string 'string1' consists of all control characters. The string 'string2' does not consist of all control characters.