array ( 0 => 'index.php', 1 => 'PHP Manual', ), 'head' => array ( 0 => 'UTF-8', 1 => 'en', ), 'this' => array ( 0 => 'function.is-string.php', 1 => 'is_string', ), 'up' => array ( 0 => 'ref.var.php', 1 => 'Variable handling Functions', ), 'prev' => array ( 0 => 'function.is-scalar.php', 1 => 'is_scalar', ), 'next' => array ( 0 => 'function.isset.php', 1 => 'isset', ), 'alternatives' => array ( ), 'source' => array ( 'lang' => 'en', 'path' => 'reference/var/functions/is-string.xml', ), ); $setup["toc"] = $TOC; $setup["toc_deprecated"] = $TOC_DEPRECATED; $setup["parents"] = $PARENTS; manual_setup($setup); ?>
(PHP 4, PHP 5, PHP 7, PHP 8)
is_string — Find whether the type of a variable is string
value
The variable being evaluated.
Example #1 is_string() example
<?php
$values = array(false, true, null, 'abc', '23', 23, '23.5', 23.5, '', ' ', '0', 0);
foreach ($values as $value) {
echo "is_string(";
var_export($value);
echo ") = ";
echo var_dump(is_string($value));
}
?>
The above example will output:
is_string(false) = bool(false) is_string(true) = bool(false) is_string(NULL) = bool(false) is_string('abc') = bool(true) is_string('23') = bool(true) is_string(23) = bool(false) is_string('23.5') = bool(true) is_string(23.5) = bool(false) is_string('') = bool(true) is_string(' ') = bool(true) is_string('0') = bool(true) is_string(0) = bool(false)