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ctype_space

(PHP 4 >= 4.0.4, PHP 5)

ctype_space -- Check for whitespace character(s)

说明

bool ctype_space ( string text )

Checks if all of the characters in the provided string, text, creates whitespace.

参数

text

The tested string.

返回值

Returns TRUE if every character in text creates some sort of white space, FALSE otherwise. Besides the blank character this also includes tab, vertical tab, line feed, carriage return and form feed characters.

范例

例子 1. A ctype_space() example

<?php
$strings = array('string1' => "\n\r\t", 'string2' => "\narf12", 'string3' => '\n\r\t');
foreach ($strings as $name => $testcase) {
    if (ctype_space($testcase)) {
        echo "The string '$name' consists of all whitespace characters.\n";
    } else {
        echo "The string '$name' does not consist of all whitespace characters.\n";
    }
}
?>

上例将输出：

The string 'string1' consists of all whitespace characters.
The string 'string2' does not consist of all whitespace characters.
The string 'string3' does not consist of all whitespace characters.

参见

ctype_cntrl()
ctype_graph()
ctype_punct()


add a note add a note User Contributed Notes
Wes Peters
29-Apr-2004 09:02
ctype_space returns TRUE for a zero-length string.  This makes it very handy for checking for empty submissions when browsers often return extraneous whitespace in empty-looking TEXTAREA controls.

(see also http://bugs.php.net/30945)
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ctype_punct上一级ctype_upper