ctype_digit

Check for numeric character(s) (PHP 4 >= 4.0.4, PHP 5)
bool ctype_digit ( string text )

Checks if all of the characters in the provided string, text, are numerical.

参数

text

The tested string.

返回值

Returns TRUE if every character in text is a decimal digit, FALSE otherwise.

范例

例 382. 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";
   }
}
?>

上例将输出:

The string 1820.20 does not consists of all digits.
The string 10002 consists of all digits.
The string wsl!12 does not consists of all digits.