I wonder if it's posible to get all the exceptions throwed.
public function test()
{
$arrayExceptions = array();
try {
throw new Exception('Division by zero.');
throw new Exception('This will never get throwed');
}
catch (Exception $e)
{
$arrayExceptions[] = $e;
}
}
I have a huge try catch block but i want to know all the errors, not only the first throwed. Is this possible with maybe more than one try or something like that or i am doing it wrong?
Thank you
You wrote it yourself: "This will never get throwed" [sic].
Because the exception will never get thrown, you cannot catch it. There only is one exception because after one exception is thrown, the whole block is abandoned and no further code in it is executed. Hence no second exception.
Maybe this was what the OP was actually asking for. If the function is not atomic and allows for some level of fault tolerance, then you can know all the errors that occurred afterwards instead of die()ing if you do something like this:
public function test()
{
$arrayExceptions = array();
try {
//action 1 throws an exception, as simulated below
throw new Exception('Division by zero.');
}
catch (Exception $e)
{
//handle action 1 's error using a default or fallback value
$arrayExceptions[] = $e;
}
try {
//action 2 throws another exception, as simulated below
throw new Exception('Value is not 42!');
}
catch (Exception $e)
{
//handle action 2 's error using a default or fallback value
$arrayExceptions[] = $e;
}
echo 'Task ended. Errors: '; // all the occurred exceptions are in the array
(count($arrayExceptions)!=0) ? print_r($arrayExceptions) : echo 'no error.';
}
Related
Here is my code:
try {
if ( condition 1 ) {
throw;
} else {
// do something
}
// some code here
if ( condition 2 ){
throw;
}
} catch (Exception $e) {
echo "something is wrong";
}
As you see, my catch block has its own error message, And that message is a constant. So really I don't need to pass a message when I use throw like this:
throw new Exception('error message');
Well can I use throw without anything? I just need to jump into catch block.
Honestly writing an useless error message is annoying for me.
As you know my current code has a syntax error: (it referring to throw;)
Parse error: syntax error, unexpected ';' in {path}
message parameter is optional in the Exception constructor. So if you don't have/want to put - just don't:
throw new Exception;
But you still must throw an instance of the Exception class (or a class that extends it), since it is a part of the php language syntax.
If you want all your exceptions to have the same message, you can extend it and define the message in your class:
class AmbiguousException extends Exception {
public function __construct($message = 'Something is wrong.', $code = 0, Exception $previous = null) {
parent::__construct($message, $code, $previous);
}
}
Then:
throw new AmbiguousException();
You can use the below throw everytime you need.
throw new Exception();
and catch will remain same as your code.
As stated in the PHP manual:
The thrown object must be an instance of the Exception class or a subclass of Exception. Trying to throw an object that is not will result in a PHP Fatal Error.
You can throw an exception without any message:
throw new Exception();
Perhaps something to help you from duplicating the same exception is as follows:
$e = new Exception('something is wrong');
try {
throw $e;
} catch (Exception $ex) {
echo $ex->getMessage();
}
You can create an instance with default message and then throw that instance.
$Exception = new Exception("some error message!");
try {
throw $Exception;
} catch (Exception $ex) {
var_dump($ex);
}
You cannot use the throw keyword on its own. However, you can use throw new Exception(); without specify the $message parameter, because it'll just fallback to the default message. Check out the Exceptions section in the PHP manual: http://php.net/manual/en/language.exceptions.extending.php
Suppose to have a PHP code inside a try...catch block. Suppose that inside catch you would like to do something (i.e. sending email) that could potentially fail and throw a new exception.
try {
// something bad happens
throw new Exception('Exception 1');
}
catch(Exception $e) {
// something bad happens also here
throw new Exception('Exception 2');
}
What is the correct (best) way to handle exceptions inside catch block?
Based on this answer, it seems to be perfectly valid to nest try/catch blocks, like this:
try {
// Dangerous operation
} catch (Exception $e) {
try {
// Send notification email of failure
} catch (Exception $e) {
// Ouch, email failed too
}
}
You should not throw anything in catch. If you do so, than you can omit this inner layer of try-catch and catch exception in outer layer of try-catch and process that exception there.
for example:
try {
function(){
try {
function(){
try {
function (){}
} catch {
throw new Exception("newInner");
}
}
} catch {
throw new Exception("new");
}
}
} catch (Exception $e) {
echo $e;
}
can be replaced to
try {
function(){
function(){
function (){
throw new Exception("newInner");
}
}
}
} catch (Exception $e) {
echo $e;
}
You have 2 possible ways:
You exit the program (if it is severe) and you write it to a log file and inform the user.
If the error is specifically from your current class/function,
you throw another error, inside the catch block.
You can use finally. Code in this branch will be executed even if exception is thrown within catch branch
I have a problem where I want to catch all exception except descendants of my custom exception.
Maybe bad design, but here it is (Simplified and names changed, but the code is quite accurate):
function doStuff()
{
try {
// code
if (something) {
// manually throw an exception
throw StuffError("Something is bad.");
}
// a third-party code, can throw exceptions
LibraryClass::arcaneMagic();
} catch (Exception $e) {
throw new StuffError("Error occured while doing stuff: "
. $e->getMessage());
}
}
/** My custom exception */
class StuffError extends Exception
{
function __construct($msg) {
parent::__construct('StuffError: ' . $msg);
}
}
However, the issue here is that I don't want the try-catch to intercept the manually throws StuffError. Or, seamlessly rethrow it or something.
As it is now, I'd get:
StuffError: Error occured while doing stuff: StuffError: Something is bad.
I want just:
StuffError: Something is bad.
How would I do it?
You can have multiple catch clauses, and the first one that matches will be the one that runs. So you could have something like this:
try {
do_some_stuff();
}
catch (StuffError $e) {
throw $e;
}
catch (Exception $e) {
throw new StuffError(Error occurred while doing stuff: " . $e->getMessage());
}
But you might want to rethink wrapping stuff like this. It obscures the real cause of the error. For one thing, you lose the stack trace. But it also complicates error handling, since now someone can't differentiate exception types the way you're trying to do, short of trying to parse the exception message (which is rather an anti-pattern in itself).
I might be misinterpreting you, but I think this is what you're looking for:
...
} catch (Exception $e) {
if (get_class($e) == 'StuffError' || is_subclass_of($e, 'StuffError')) {
throw $e;
} else {
throw new StuffError("Error occured while doing stuff: "
. $e->getMessage());
}
}
...
Replace your catch statement with the code above. It checks to see if the exception is a StuffError or a child class of StuffError. I'm still very confused at why you would need to throw a StuffError exception after you catch, but maybe that's just some weirdness coming from translating/cleaning your code.
This question is about the best way to execute code outside of try block only if no exception is thrown.
try {
//experiment
//can't put code after experiment because I don't want a possible exception from this code to be caught by the following catch. It needs to bubble.
} catch(Exception $explosion) {
//contain the blast
} finally {
//cleanup
//this is not the answer since it executes even if an exception occured
//finally will be available in php 5.5
} else {
//code to be executed only if no exception was thrown
//but no try ... else block exists in php
}
This is method suggested by #webbiedave in response to the question php try .. else. I find it unsatisfactory because of the use of the extra $caught variable.
$caught = false;
try {
// something
} catch (Exception $e) {
$caught = true;
}
if (!$caught) {
}
So what is a better (or the best) way to accomplish this without the need for an extra variable?
One possibility is to put the try block in a method, and return false if an exception is cought.
function myFunction() {
try {
// Code that throws an exception
} catch(Exception $e) {
return false;
}
return true;
}
Have your catch block exit the function or (re)throw/throw an exception. You can filter your exceptions as well. So if your other code also throws an exception you can catch that and (re)throw it. Remember that:
Execution continues if no exception is caught.
If an exception happens and is caught and not (re)throw or a new one throw.
You don't exit your function from the catch block.
It's always a good idea to (re)throw any exception that you don't handle.
We should always be explicit in our exception handling. Meaning if you catch exceptions check the error that we can handle anything else should be (re)throw(n)
The way I would handle your situation would be to (re)throw the exception from the second statement.
try {
$this->throwExceptionA();
$this->throwExceptionB();
} catch (Exception $e) {
if($e->getMessage() == "ExceptionA Message") {
//Do handle code
} elseif($e->getMessage() == "ExceptionB Message") {
//Do other clean-up
throw $e;
} else {
//We should always do this or we will create bugs that elude us because
//we are catching exception that we are not handling
throw $e;
}
}
i have the following code and i'm wondering if i can use try & catch as below:
class fun_database implements idbInfo{
private $srvr=idbInfo::srvr_name;
private $usr=idbInfo::usrnm;
private $pass=idbInfo::psswrd;
private $db=idbInfo::db_name;
public function connct(){
$hookup = new mysqli($this->srvr, $this->usr, $this->pass, $this->db);
if ($hookup->connect_errno)
{
throw new Exception("Error Processing Request", 1);
}
}
public function sql_require_all($table_name, $table_col){
$hookup = new connct();
$result = $hookup->query("SELECT $table_col FROM $table_name");
if($hookup->error()){
throw new Exception("Error Processing Request", 1);
}
return $result->num_rows;
}
}
This is a simple connection to the mysql and performing some querying there. Here is and the actual call of the functions above:
$conn = new fun_database();
try{
$result = $conn->sql_require_all('wordtypes', 'types');
}
catch(Exception $err){
echo "Problems at:". $err->getMessage();
}
return "<option>".$result."</option>";
What i'm asking is a bit theory. Most probably this code is NOT WORKING (i didn't test it yet). I just want to know is it possible with one 'try' to 'catch' two exceptions (as you can see the first 'throw' is in the second method of fun_database, and the second 'throw' is in the first method of the same object which is only called from the second method).
sorry for making it too complicated but still can't figure it out id this structure of try/catch is working.
you can only catch different types of exception...
class fun_database implements idbInfo{
private $srvr=idbInfo::srvr_name;
private $usr=idbInfo::usrnm;
private $pass=idbInfo::psswrd;
private $db=idbInfo::db_name;
public function connct(){
$hookup = new mysqli($this->srvr, $this->usr, $this->pass, $this->db);
if ($hookup->connect_errno)
{
throw new DomainException("Error Processing Request", 1);
}
}
public function sql_require_all($table_name, $table_col){
$hookup = new connct();
$result = $hookup->query("SELECT $table_col FROM $table_name");
if($hookup->error()){
throw new Exception("Error Processing Request", 1);
}
return $result->num_rows;
}
}
Then:
try{
$conn = new fun_database();
$result = $conn->sql_require_all('wordtypes', 'types');
}
catch(DomainException $err){
echo "This Problem at:". $err->getMessage();
}
catch(Exception $err){
echo "That Problem at:". $err->getMessage();
}
return "<option>".$result."</option>";
you would need your class instantiation inside that try block though I believe.
It wouldn't catch the two exceptions because as soon as the first exception is thrown, it goes straight to the catch block, thereby skipping the second exception directly.
You could wrap each code which may throw an exception in its own try-catch block.
Yes and no. Your code is able to catch two of this exceptions but not both of them at the same time. When one of exception will be thrown, program execution will look for closest catch block, which fits to catch Exception class. Rest of code will be omitted.
You can throw an exception at an point in the program (not after an excpetion if it is not caught).
As soon as it hits this point it will stop and try to make the fallback to the a try catch block. As soon as it finds one it will do this block (if it is a good catch)
You could make a try catch around your entire program or just a function.
You can throw different classes of exceptions:
class ConnectException extends Exception {}
class QueryException extends Exception {}
and then catch different exceptions:
try {
// something
}
catch (ConnectException $ex) {
// connect exception
}
catch (QueryException $ex) {
// query exception
}
It is not possible because when you throw
throw new Exception("Error Processing Request", 1);
this exception it will be caught in this line
catch(Exception $err){
echo "This Problem at:". $err->getMessage();
}
you will not reach the line that can throw the other exception if first exception was thrown