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For Error handling, for example, in VBA, we can have "On Error Resume Next" or "On Error Goto" to
let the program still in running even the error happen at exact line number.
In Javascript, that is also easily to understand the error handling from try and catch{}, if error happen
in try {} and then goto catch();

But for my php I am trying using try and catch{} that is NOT exactly same as method as in javascript or VBA handling.
I get  an error message from the following php code   : Fatal error: Call to a member function
getElementByTagName() on a non-object  on line 10 ,which is exact same line at $data= $dom->getElementsByTagName('table')->item(4)->getElementsByTagName('div')->item(21)>nodeValue;
In my code, I try to access the remote-site with $c varaible to program the $url, there is 10 pages I need to
grab the data, if one of fail, I will re-do it until 5 times is fail.

I don't care the fatal error but it will halt the program running or suspend everything , Why I don't care
because I know it is remote-site server is  busy only  to handle my request of LoadHTMLFile().

Now I put try and catch {} to let it re-do again for 4 more times once fatal error happen, But
it still get the same line ans same fatal error message and quit the program right away, in other words,
it never go to catch{}.

Please advise, how to let the following code running even fatal-error because I can re-do 4 more time and then
quit the program. I know at least  one time success on LoadHTMlfile() work in 5 trial.

There is a lot of  Error handling at http://php.net/manual/en/function.set-error-handler.php,
I don't how it works becuase I know once the fatal-error happen, the program will quit so how to
do any if or condition check for the error happen location.


Duncan

<?phpFor ($k=0; $k <4; ++$k)  {  //repeat loadhtmlfile() over again if one of $c is not loadedtry {for ($c=0; $c < 10; ++$c) {$url= 'http://www.othersite.com/ex.aspx?symbol='.$c;$dom = new DOMDocument();$dom->loadHTMLFile($url);echo "start=".$c;$data= $dom->getElementsByTagName('table')->item(4)->getElementsByTagName('div')->item(21)>nodeValue;echo "Sucess to pass getElementsByTagname".$c;}$k=4;//It means no need to do re-do since no fatal error during loadHTMlfile for 10 pages}catch(err) {echo "It found error at =" %c;}}?>                                  

1:2:3:4:5:6:7:8:9:10:11:12:13:14:15:16:17:18:

sorry... my fault. it must be if ($d1) and not if (!$d1) ... same for the other tests.

This is pretty unambiguous: Call to a member function getElementByTagName() on a non-object on line 10.

You would want to know what created the data you're using on line 10.  You can test to see if the data is an object with this function:
http://us3.php.net/manual/en/function.is-object.php

Probably, either something failed to create the object (and returned FALSE) in an earlier instruction, or the data you've got does not have an object at the index level you've addressed.  In either case, the right thing to do is program so that no fatal error occurs, and that means testing the data for the correct type before using it.

Here is a microcosm example of how the error happens.  Note that this is different for non-arrays and non-objects.

<?php // RAY_expected_error.phperror_reporting(E_ALL);// CREATE A NON-OBJECT (THIS IS A STRING)$foo = 'bar';// WARNING IF WE TRY TO USE WITH AN ITERATORforeach ($foo as $lump){   /* STUFF */}// FATAL ERROR IF WE TRY TO USE A NON-OBJECT WITH OOP NOTATION$thing = $foo->baz();                                          

1:2:3:4:5:6:7:8:9:10:11:12:13:

catch fatal errors:
http://stackoverflow.com/questions/277224/how-do-i-catch-a-php-fatal-error

Fatal errors in php can not be catched as they are fatal and cause an immediate aboirt of the php script.
The dom extension itself is not designed around the new features of php 5 like exceptions. So it would be cool if the dom extension would throw an exception if an element does not exists instead of reaturn a null value. So you need to code this by yourself:

$tabitems = $dom->getElementsByTagName('table');if (! ($item = $tabitems->item(4)) instanceof DOMNode)) {    throw new Exception();}$divitems = $itme->getElementsByTagName('div')if (! ($item = $divitems->item(21)) instanceof DOMNode)) {    throw new Exception();}return $item->nodeValue;                                          

1:2:3:4:5:6:7:8:9:

i see,

please put the try{} inside the loop