I have a PHP foreach from an array, the array is given to me by my DB provider via a soap web service so I cannot change the array I get. When there are no elements to return, I get an empty array, this results in
Warning: Invalid argument supplied for foreach()
the loop looks like
foreach (($point1['return']) as $val)
Where can I put an @ to stop this warning, and if I cant, what I do I do to turn off php warnings.
Hiding the warning is not the right way. You should check whether it exists and is an array.
if (is_array($point1['return'])) {
foreach ($point1['return'] as $val) {
...
}
}
Actually, turning off warnings or using the @ operator is not the right way to go 99% of the time.
Solve the problem instead of hiding it.
foreach() can handle not only arrays but also objects by either using the the default "all visible properties" implementation or a custom implementation via the traversable/iterator interface.
And a "DB provider via a soap web service" is something where I'd keep an eye on the possibility of (suddenly) having an object/iterator instead of a plain array.
So, if you're going to test the existence and data type before passing the variable to foreach, you should consider not only testing for is_array() but also for instanceof Traversable.
<?php
class Foo implements Iterator {
protected $v = 0;
public function current() { return $this->v; }
public function key() { return $this->v; }
public function next() { ++$this->v; }
public function rewind() { $this->v=0; }
public function valid() { return 10>$this->v; }
}
//$a = array(1,2,3,4);
$a = new Foo;
if( is_array($a) || $a instanceof Traversable ) {
foreach($a as $e) {
echo $e, "\n";
}
}
An empty array does not cause that error, the problem is that you are trying to iterate trough something that is not an array. You could add a check using is_array function.
Better to let errors display but check that the input is an array first. So you could wrap the foreach in an if, like this:
if ((is_array($point1)) && (is_array($point1['return']))) {
foreach (($point1['return']) as $val)
...
}
Check first for an array:
if(is_array($point1['return']))
{
...
}
You can also explicitly cast the argument to array:
foreach ((array) $point1['return'] as $val) {
Note: this still will issue undefined index, if there is no 'return' key in $point1
Check whether that is actually an array. with is_array(); !!
There's no need to suppress the warning.
As a matter of fact, It's not possible to suppress that invalid argument warning.
Paste this into your function file:
set_error_handler(function($errno, $errstr){
if(stristr($errstr,'Invalid argument supplied for foreach()')){
return true;
}
return false;
});
