Why does var_dump(array) result in a 500 error in Magento?

I'm trying to see what is inside all the objects of the Magento system, but when I try to var_dump the $_links vari开发者_运维技巧able (containing all information needed for rendering the links in the header of every page) from inside the top links template, my server responds with a 500 error. Anyone know why?

Dumps of Magento objects get a bit messy, even if there isn't recursion there is all the EAV and cache stuff. When you have an array you'll need to dump them individually:

foreach ($_links as $object) {
    var_dump($object->debug());
}

It's likely a memory error. Magento's object can be huge, and the default var_dump implementation in PHP isn't that smart about some of the circular references.

Install xDebug is a must. With xDebug, the var_dump function gets a lot smarter, and the memory limit exhausted errors mostly go away.

Magento is a huge memory hog. Most likely, you're running out of available memory.

Instead of var dumping the object itself, dump the objects data using its ->toArray() method. Note: all Mage_ objects inherit this method.

HTTP 500 errors will occur in scenarios like this when PHP spewed an error, and you did not configure your setup to display it to the user.

Look in your error log (something like /var/lib/httpd/log/error_log) to find out what's actually going on.

Possibilities include:

• Syntax error
• Headers already sent before output
• Memory exhaustion from printing huge variable

In most of cases it's because $_links variable contains a lot of huge nested objects. Try the xDebug extension for PHP - it allows to tune var_dump output to limit nesting level and amount of displaying data.

$_link variable consist huge number of objects inside, we needs to debug to print the object

print_r($_link->debug());
(or)
var_dump($_link->debug());

I solve my var_dump(array) result in a 500 error in Magento2 issue as below(May be someone help)

//app/code/MyCompany/Shipping/view/adminhtml/templates/order/view/items.phtml

foreach ($_items as $_item):
    echo "<pre>";
    var_dump($_item->debug());
    echo "</pre>";

Sample Output: