Returns true, if the string is empty, too.
is_string
(PHP 4, PHP 5)
is_string — 変数が文字列かどうかを調べる
説明
bool is_string ( mixed $var )指定した変数が文字列かどうかを調べます。
パラメータ
- var
評価する変数。
返り値
var が string である場合に TRUE、それ以外の場合に FALSE を返します。
参考
| is_float() |
| is_int() |
| is_bool() |
| is_object() |
| is_array() |
is_string
djhook at users dot sourceforge dot net
12-Sep-2003 11:20
12-Sep-2003 11:20
function is_upper($input) {
return ($input == strtoupper($input));
}
function is_lower($input) {
return ($input == strtolower($input));
}
this functions check if a string is all upper/lower case.
input: string
output: true/false
slicky at newshelix dot com
20-Mar-2001 10:06
20-Mar-2001 10:06
Be aware that this function could result into unwanted results if you check single chars in an array.
For instance:
You have a simple string and want to repeat this string evertime it ends.
<p>for ($i=0; $i < strlen($string);$i++){
if(!is_string($key[$x]))
$x = 0;
echo $key[$x];
$x++;
}
</p>This will print you out the key, but won't iterate it since $x won't be reset. is_string function will give out true at element in that string, even if it doesn't exist. for instance is_string $key[1000] while your string is just 10chars long.
However this doesn't matter just use $key[$x] == '' instead.
Of course you won't use this to iterate a string, but you might come across something where this get useful, for instance for a en/decrypt engine.