PHP : If...Else...Query - php

Question

I am executing this statement under while (($data=fgetcsv($this->fin,5000,";"))!==FALSE)
Now what I want in else loop is to throw exception only for data value which did not satisfy the if condition. Right now am displaying the complete row as I am not sure how to throw exception only for data which does not satisfy the value.
Code
if ((strtotime($data[11]) &&strtotime($data[12])&&strtotime($data[16]))!==FALSE
&& ctype_digit($data[0]) && ctype_alnum($data[1]) && ctype_digit($data[2])
&& ctype_alnum($data[3]) && ctype_alnum($data[4]) && ctype_alnum($data[5])
&& ctype_alnum($data[6]) && ctype_alnum($data[7]) && ctype_alnum($data[8])
&& $this->_is_valid($data[9]) && ctype_digit($data[10]) && ctype_digit($data[13])
&& $this->_is_valid($data[14]))
{
//Some Logic
}
else
{
throw new Exception ("Data {$data[0], $data[1], $data[2], $data[3],
$data[4], $data[5], $data[6], $data[7],
$data[8], $data[9], $data[10], $data[11], $data[12],
$data[13], $data[14], $data[16]} is not in valid format");
}
Guidance would be highly appreciated as to how can I throw exception only for data which did not satisfy the if value.

Answer 1

Why not separate the tests ? i.e. do each test one by one, and throw an exception if a specific test fails ?
Copy-pasting from your code, it would probably look like this :
if (!strtotime($data[11])) {
throw new Exception("field 11 : {$data[11]} is not a valid date");
}
if (!strtotime($data[12])) {
throw new Exception("field 12 : {$data[12]} is not a valid date");
}
// Some more...
if (!ctype_alnum($data[8])) {
throw new Exception("field 8 : {$data[8]} is not a valid alnum");
}
// And so on...
// And when all is tested, you know the items
// in $data are all OK
This way :
You can know which field caused a validation failure
If you have several distinct tests on the same field, you can know which specific test failed
And, as a possibility, you could (if needed) thrown different kind of exceptions, depending on the test that failed (i.e. one kind of exception for dates, one for integers, ...) -- in some cases, that might be useful.
Edit after the comment : more full example
Yes, you can validate field by field, and still work line by line.
You just have to wrap your testing code in a try/catch block, that's inside the loop that goes line by line ; a bit like that :
$validData = array();
$errors = array();
while ($data = fgetcsv($f)) {
try {
// Validate the data of the current line
// And, if valid, insert it into the database
if (!strtotime($data[11])) {
throw new Exception("field 11 : {$data[11]} is not a valid date");
}
if (!strtotime($data[12])) {
throw new Exception("field 12 : {$data[12]} is not a valid date");
}
// Some more...
if (!ctype_alnum($data[8])) {
throw new Exception("field 8 : {$data[8]} is not a valid alnum");
}
// And so on...
// And when all is tested, you know the items
// in $data are all OK
// => which means it can be inserted into the DB
// Or you can just put the valid data into a "temporary" array, that will be used later :
$validData[] = $data;
} catch (Exception $e) {
// An error has occurend on the current line
// You can log it, if necessary :
$errors[] = $e->getMessage();
}
}
// Now that the whole file has been read, test if there's been an error :
if (empty($errors)) {
// No error
// => insert the data that's in $validData
} else {
// There's been an error
// => don't insert the data that's in $validData, if you don't want to insert anything
}
With that :
If there is an exception on one line (i.e. validation fails), you'll jump to the catch block, to deal with the problem
And the loop will then restart, for the next line.
EDIT: (By Yacoby)
Rather than having endless if statments, you could just define which elements should be checked by which function and then process them in a loop. That way it avoids having 16 if statements.
Code example:
foreach ( array(11,12,16) as $index ){
if ( !strtotime($data[$i]) ){
throw new Exception("field {$i} : {$data[$i]} is not a date");
}
}
foreach ( array(1,3,4,5,6,7,8) as $index ){
if ( !ctype_alnum($data[$i]) ){
throw new Exception("field {$i} : {$data[$i]} is not alphanumeric");
}
}
foreach ( array(2, 10) as $i ){
if ( !ctype_digit($data[$i]) ){
throw new Exception("field {$i} : {$data[$i]} is not a valid digit");
}
}
if ( !$this->_is_valid($data[14]) ){
throw new Exception("field {14} : {$data[14]} is not valid");
}

Answer 2

You'll need to break up your massive if statement into one per value.

Answer 3

I think you'd be better off breaking this up into many if statements like
if(!strtotime($data[11])
{
throw new Exception("...");
}
if(!strtotime($data[12]))
{
throw new Exception("...");
}
//after all of your if statements now do business logic
//remember that all of your if conditions have to be met to get this far
//because throwing the exception will leave this stack
//so it functions sort of like the else clause would.