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ctype_cntrl

(PHP 4 >= 4.0.4, PHP 5)

ctype_cntrl -- Check for control character(s)

说明

bool ctype_cntrl ( string text )

Checks if all of the characters in the provided string, text, are control characters. Control characters are e.g. line feed, tab, esc.

参数

text

The tested string.

返回值

Returns TRUE if every character in text is a letter from the current locale, FALSE otherwise.

范例

例子 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";
    }
}
?>

上例将输出：

The string 'string1' consists of all control characters.
The string 'string2' does not consists of all control characters.

参见

ctype_print()


add a note add a note User Contributed Notes
Simon Hartley - srhartley at hotmail dot com
12-Apr-2004 11:15
When evaluting a string for control characters ensure that the string is surrounded by double (not single quotes).
add a note add a note


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