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<?php
/* Åжϳ£Á¿ÊÇ·ñ´æÔÚ*/
if (defined('MYCONSTANT')) {
echo MYCONSTANT;
}
//ÅжϱäÁ¿ÊÇ·ñ´æÔÚ
if (isset($myvar)) {
echo "´æÔÚ±äÁ¿$myvar.";
}
//ÅжϺ¯ÊýÊÇ·ñ´æÔÚ
if (function_exists('imap_open')) {
echo "´æÔÚº¯Êýimag_open\n";
} else {
echo "º¯Êýimag_open²»´æÔÚ\n";
}
//ÅжÏÀàÊÇ·ñ´æÔÚ
if (class_exists('MyClass')) {
$myclass = new MyClass();
}
//ÅжÏÎļþÊÇ·ñ´æÔÚ
$filename = '/path/to/foo.txt';
if (file_exists($filename)) {
echo "The file $filename exists";
} else {
echo "The file $filename does not exist";
}
//ÅжÏÊý×éÖÐÊÇ·ñ´æÔÚij³ÉÔ±
$os = array("Mac", "NT", "Irix", "Linux");
if (in_array("Irix", $os)) {
echo "Got Irix";
}
//ÅжϱäÁ¿ÀàÐÍ
is_array()
is_bool()
is_float()
is_integer()
is_null()
is_numeric()
is_object()
is_resource()
is_scalar()
is_string()
?>