php判断 !==false

$res = 0;
if($res !== false){
echo "0数字通过<br>";
}else{
echo "0数字不通过<br>";
}

$res = "0";
if($res !== false){
echo "0字符串通过<br>";
}else{
echo "0字符串不通过<br>";
}

$res = NULL;
if($res !== false){
echo "NULL通过<br>";
}else{
echo "NULL不通过<br>";
}

$res = "";
if($res !== false){
echo "空字符串通过<br>";
}else{
echo "空字符串不通过<br>";
}

$res = array();
if($res !== false){
echo "array()通过<br>";
}else{
echo "array()不通过<br>";
}

$res = FALSE;
if($res !== false){
echo "FALSE通过<br>";
}else{
echo "FALSE不通过<br>";
}

$res = TRUE;
if($res !== false){
echo "TRUE通过<br>";
}else{
echo "TRUE不通过<br>";
}