Laravel & PHP: Cannot reach array items without a trick, why is that? - php

Question

Introduction to the problem
I have written a class to import a specific CSV file. This class handles everything except moving and reading the imported file. This is done in the controller by using de File facade in Laravel.
The description below only describes one of the arrays, but I use more arrays, and also in the class itself I get the same problem. The problem is that the app crashes with some obscure error everytime I try to access an item in the array by using a string as key value. I tested this in a seperate, non-laravel, php-file and there I don't get an error. It's only in my Laravel app. Strange thing is that I tested the arrays the following way:
a) using array_key_exists - No keys are found (I used both ' and ")
b) using array_keys - This time I get all the keys from the array
c) for example: $report['student_number'] - Doesn't work, I get an error here
d) for example: $report[array_keys($report)[0]] - This works
e) In vanilla PHP I do the same and there I do not get any errors.
The real code
In the controller I handle the upload the following way:
$uploaded_file = $request->file('uploadfile');
$uploaded_file->move(storage_path().'/files', $uploaded_file->getClientOriginalName());
$import_file = storage_path().'/files/'.$uploaded_file->getClientOriginalName();
if(File::exists($import_file) && File::isReadable($import_file)) {
$raw_file_data = File::get($import_file);
$import = ImportStudents::getInstance();
$import_result = $import->import($raw_file_data);
}
In the Import class I have a private property:
private $report = [];
I fill the array with data the following way:
$this->report[$student_number][] = [
'field' => $field,
'db_field' => 'student_number',
'new_value' => $value,
'old_value' => $student_number,
'action' => 'updated'
];
In the class I finaly return this array to the controller:
return $this->report;
In the controller I pass this array to the view:
return view('home.import_report')->with('report', $import_result);
In the blade file I use the following code:
#foreach($report as $report_row)
<td>{{ $report_row['field'] }}</td>
<td>{{ $report_row['db_field'] }}</td>
<td>{{ $report_row['new_value'] }}</td>
<td>{{ $report_row['old_value'] }}</td>
<td>{{ $report_row['action'] }}</td>
#endforeach
The error
The "C:\Windows\Temp\php57CD.tmp" file does not exist or is not
readable.
Remarks
Above is only one part in my code where I get the error. As I mentioned before, I also get the same error in the code of the class.
Specifications
Laravel: 6.x
PHP: 7.3.10
Question
What am I overlooking here? What is the problem?

Answer 1

The solution for the above mentioned problem with showing the report, how could I forget, that I needed an extra foreach loop.
Old code
#foreach($report as $report_row)
<td>{{ $report_row['field'] }}</td>
<td>{{ $report_row['db_field'] }}</td>
<td>{{ $report_row['new_value'] }}</td>
<td>{{ $report_row['old_value'] }}</td>
<td>{{ $report_row['action'] }}</td>
#endforeach
The answer was so obvious already in my own code :-(, this code:
$this->report[$student_number][] = [
'field' => $field,
'db_field' => 'student_number',
'new_value' => $value,
'old_value' => $student_number,
'action' => 'updated'
];
New code (solution)
#forelse($report as $student_number => $report_row)
<tr><td colspan="6" style="color: white; background-color: darkblue; padding: 0;"><h5>{{ $student_number }} - {{ $report_row[0]['name'] }}</h5></td></tr>
#foreach($report_row as $actions)
<tr>
<td></td>
<td>{{ $actions['field'] }}</td>
<td>{{ $actions['db_field'] }}</td>
<td>{{ $actions['new_value'] }}</td>
<td>{{ $actions['old_value'] }}</td>
<td>{{ $actions['action'] }}</td>
</tr>
#endforeach
#empty
<tr><td colspan="6">No changes</td></tr>
#endforelse
But this problem still exists with arrays
a) using array_key_exists - No keys are found (I used both ' and ")
b) using array_keys - This time I get all the keys from the array
c) for example: $report['student_number'] - Doesn't work, I get an error here
d) for example: $report[array_keys($report)[0]] - This works
e) In vanilla PHP I do the same and there I do not get any errors.
What's not working
$student->first_name = $imported_row['Roepnaam'];
But the key 'Roepnaam' does exist in the array.
With array_keys($imported_row) I can see that the key exists.
What is working
$student->first_name = $imported_row[array_keys($imported_row)[1]];
This what puzzles me!