(PHP 4 >= 4.0.4, PHP 5)
ctype_cntrl — Check for control character(s)
$text
)
Checks if all of the characters in the provided string,
text, are control characters.
Control characters are e.g. line feed, tab, escape.
text
The tested string.
Returns TRUE if every character in text is
a control character from the current locale, FALSE otherwise.
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";
}
}
?>
以上例程会输出：
The string 'string1' consists of all control characters. The string 'string2' does not consist of all control characters.
Note:
如果给出一个 -128 到 255 之间(含)的整数, 将会被解释为该值对应的ASCII字符 (负值将加上 256 以支持扩展ASCII字符). 其它整数将会被解释为该值对应的十进制字符串.