In JavaScript the statement evaluates to

true

but in PHP it evaluates to

false

if ("0") {
    
}

If a fatal error occurs catch block calls

logError

function and passes details of the error, such as:

file

,

line

,

code

,

message

and

trace

try {
    undefinedFunction();
} catch (Error $e) {
    logError(
		'ERR FILE: ' . $e->getFile() . "\n" .
		'ERR LINE: ' . $e->getLine() . "\n" .
		'ERR CODE: ' . $e->getCode() . "\n" .
		'ERR TEXT: ' . $e->getMessage() . "\n" .
		'ERR TRACE String: ' . $e->getTraceAsString()
	);
}

The function

logError

appends current date and time to the error details and logs into the error file

function logError($error) {
	
	$content = "\n\n\n".date('Y-m-d H:i:s');
	$content .= "\n".$error;
	
	file_put_contents('/var/log/errors.txt', $content, FILE_APPEND);
}

Function

splice

changes content of an array. Let's first create an array of integers

let myFavoriteNumbers = [5, 14, 16, 18, 23, 25, 27, 50, 70]

If we want to remove one element from an array, we need to pass

1

as the second argument and the index of the item as the first argument. In this example

14

(second item) will be removed by passing

1 and 1

as arguments

myFavoriteNumbers.splice(1, 1);  // [5, 16,18, 23, 25, 27, 50, 70]

To remove two adjacent items, we need to pass first item's index

2

and quantity of items

2

that we want to remove. In this example we want to remove

18

and

23

from the array at the same time

myFavoriteNumbers.splice(2, 2);  // [5, 16, 25, 27, 50, 70]

Replaces 3 items starting from index 2 with

27

,

29

and

31

myFavoriteNumbers.splice(2, 2, 27, 29, 31);  // [5, 16, 27, 29, 31, 50, 70]

Removes all the items of the array except the first and the last items

myFavoriteNumbers.splice(1, 5);  // [5,70]

Adds the two new items

100

and

200

to the array after the first item

myFavoriteNumbers.splice(1, 0, 100, 200);  // [5, 100, 200, 70]

PHP 7.0 + can handle fatal errors without terminating PHP process. It means we can catch the fatal error using

catch

block

try {
    undefinedFunction();
} catch (Error $e) {
    echo 'Fatal error occurred: ' . $e->getMessage();
}

After running the above code on PHP 7+ the result will be:

Fatal error occurred: Call to undefined function undefinedFunction()

If we run the same code on PHP 5.6, we will get the following result:

<br />
<b>Fatal error</b>:  Call to undefined function undefinedFunction() in <b>[...][...]</b> on line <b>5</b><br />

Let's declare any string variable

let myString = 'Some String'

The string variable has access to all

string functions

document.write(myString.toUpperCase());

The result will be:

SOME STRING

But if we let number variable to use the string function

toUpperCase()

let myNumber = 55
console.log(myNumber.toUpperCase());

Then we will get the following error. This is because number type variable does not have access to string functions

Uncaught TypeError: myNumber.toUpperCase is not a function

Creates

myFavoriteNumbers

array

let myFavoriteNumbers = [5, 14, 16, 18]

Adds new item

22

to the array

myFavoriteNumbers.push(22)

Adds the array as a new item to the

myFavoriteNumbers

array

myFavoriteNumbers.push([23, 24])

Adds the object to the array as new item

myFavoriteNumbers.push({firstNumber: 25, secondNumber: 26})

Adds the function to the array as new item

myFavoriteNumbers.push(function(){console.log('I am fired!')})

Adds new string item to the array

myFavoriteNumbers.push('27')

Let's fire the function that we added as an item

myFavoriteNumbers[7]()

After running the function the result will be:

I am fired!

Creates array of numbers;

let myFavoriteNumbers = [5, 14, 16, 27]

Creates array of strings

let myFavoriteColors = ['green', 'yellow', 'red']

Creates array of arrays

let myMatrix = [
    [12, 23, 34], 
    [13, 35, 57], 
    [14, 47, 70], 
]

Creates array of objects

let myFavoritePlanets = [
    {name: 'Earth', radius: 6371}, 
    {name: 'Jupiter', radius: 69911}, 
    {name: 'Neptune', radius: 24622, moons: ['Triton', 'Thalassa', 'Nereid', 'Proteus', 'Hippocamp', 'Naiad']}
]

Accessing one of the moons of Neptune

console.log(myFavoritePlanets[2].moons[4])

The

json

method creates a

JSON

equivalent column. We can use

 $table->json('options');

to store json data in database

We need to follow the rules if we want our passwords to be strong enough

1. Contains at least 8 characters
2. Contains at least one uppercase letter
3. Contains at least one lowercase letter
4. Contains at least one number
5. Contains at least one special character

While sending ajax we can convert object into a string with

JSON.stringify()

function...

$.ajax({
            url: '/api/page/delete',
            type: 'DELETE',
            data: JSON.stringify({
                'id': id,                   
                 '_token': ' {{ csrf_token() }} '
             }),

Then parse the result to reach data item:

success: function(result) {
                    parsed_result = JSON.parse(result)
                    items = parsed_result.data.items
}