02/06/2010
0
This JavaScript article lists some comparisons between two popular web programming languages in the world of open source: JavaScript and PHP. The comparisons in this JavaScript tutorial focus on Variables, Object and Array, Control Structures; from this list, the web coders (programmers) have a look about them more accurate, and may give the appropriative solutions for the requirements of their tasks.
- Demo
- Enlarge
- Reload
- New window
Generate your business videos by AI with voice or just text
Your first FREE AI Video App! Automate Your First AI Video. Create Your Professional Video In 5 Minutes By AI No Equipment Or Video Editing Skill Requred. Effortless Video Production For Content Marketers.
This is a basic comparison between PHP and JavaScript. It's intended for users familiar with PHP and looking for JavaScript equivalents.
JavaScript and PHP Comparisons:
Variables
Variable Scope
PHP and JavaScript take two very different approaches to declaring variables. In PHP, all variables are local in scope unless declared as global. JavaScript is opposite, and all variables are global unless declared with the var keyword.
PHP
<?php
function foo() {
$variable_a = 'value'; // Local variable declaration.
}
function bar() {
print $variable_a; // Prints nothing.
}
function foo() {
global $variable_b; // Global variable declaration.
$variable_b = 'value';
}
function bar() {
global $variable_b;
print $variable_b; // Prints 'value'.
}
?>JavaScript
function foo() {
var variableA = 'value'; // Local variable with use of "var".
}
function bar() {
alert(variableA); // Variable not defined error.
}
function foo() {
variableB = 'value'; // Global variable, no "var" declaration.
}
function bar() {
alert(variableB); // alert('value')
}An interesting twist is JavaScript also allows scoping within functions. When using the "var" declaration, variables are available for everything in the current function or any sub-functions.
PHP
function foo() {
$variable_a = 'value'; // Local variable declaration.
function bar() {
print $variable_a; // Prints nothing.
}
}JavaScript
function foo() {
var variableA = 'value'; // Local variable with use of "var".
function bar() {
alert(variableA); // alert('value');
}
}Variable Types
Both PHP and JavaScript are loosely typed, meaning a variable can be of any type, and change from one type to another. However both PHP and JavaScript keep track of the type of variables, and you can check this type.
PHP
<?php
$foo = 3;
is_int($foo); // TRUE
$foo = '3';
is_int($foo); // FALSE
is_string($foo); // TRUE
?>JavaScript
var foo = 3;
type_of(foo); // 'number'
foo = '3';
type_of(foo); // 'string'Casting Variables
Every now and then you might need to cast variables to a specific
type. This is extremely important when dealing with JavaScript's + operator, which is used for both string concatenation and for numeric addition.
PHP
In PHP, variables may be cast to certain type by using parenthesis. String concatenation is done with "." and addition with "+".
<?php
$foo = '3.5 kg';
$bar = (float)$foo; // 3.5
$bar = (int)$foo; // 3
$baz = (string)$foo; // '3.5 kg'
print $bar + $baz; // 6
print $bar . $baz; // '33'
?>JavaScript
JavaScript has functions specifically for casting variables to numbers.
Both string concatenation and addition is done with "+". If mixing a
string and a number with "+", concatenation will take precedence over
addition.
var foo = '3.5 kg';
var bar = parseFloat(foo); // 3.5
bar = parseInt(foo); // 3
var baz = '3';
alert(bar + baz); // '33'
alert(bar + parseInt(baz)); // 6 Checking for NULL or empty() values
Variables in PHP don't have to be defined for you to use them, though if you're working with E_ALL compliance on (not the default of most PHP installs), your script will throw a notice if you try to use an undeclared variable. JavaScript is a bit mixed concerning undeclared variables, if you attempt to modify or compare with an undeclared variable, the script will break entirely, but you can check the variable status using typeof() or in conditional statements containing only that variable.
PHP
<?php
// Check if a variable is declared at all.
if (!isset($foo)) {
$foo = TRUE;
}
// Or check if a variable has a value that equates to FALSE.
// This includes variables that have not been declared.
if (empty($bar)) {
$bar = TRUE;
}
?>JavaScript
// Check if a variable is declared at all.
if (typeof(foo) == 'undefined') {
var foo = true;
}
// Or check if a variable has a value that equates to false.
// This includes variables that have not been declared.
if (!bar) {
var bar = true;
}
// However an undeclared variable can't be used in comparisons.
if (baz == false) { // Variable undefined error.
var baz = true;
}Boolean Variables
A simple but important thing to remember is that JavaScript only recognizes the keyword true in all lowercase. PHP accepts both uppercase and lowercase.
PHP
<?php
is_boolean(TRUE); // TRUE
is_boolean(true); // TRUE
is_boolean(True); // TRUE
?>JavaScript
typeof(true); // 'boolean'
typeof(TRUE); // 'undefined'
typeof(True); // 'undefined'Case Sensitivity
Both JavaScript and PHP are case sensitive in their variables. PHP is not case-sensitive in function or class declarations, but JavaScript is case sensitive for these also.
PHP
<?php
// Variable case:
$foo = 'bar';
print $foo; // Prints 'bar'.
print $Foo; // Prints nothing.
// Function case:
function foo() {
print 'bar';
}
foo(); // Prints 'bar'.
Foo(); // Prints 'bar'.
?>JavaScript
// Variable case:
var foo = 'bar';
alert(foo); // alert('bar')
alert(Foo); // Variable not defined error.
// Function case:
function foo() {
alert('bar');
}
foo(); // alert('bar')
Foo(); // Function not defined error.
by Preview- Sent (0)
- New
Generate your business videos by AI with voice or just text
chatGPTaz.com
Talk to ChatGPT by your mother language
AppAIVideo
Your first FREE AI Video App
Deepfake Video
Deepfake AI Video Maker
Deepfake
Deepfake AI Video Maker
AI Deep Fake
Deepfake AI Video Maker
AI Voice Generator
Most Realistic Text to Speech AI Solutions
AI Voice Generator
Most Realistic Text to Speech AI Solutions
AIvidio
AI Video Mobile Solutions
AIvideos
AI Video Platform & Solutions
AIvedio
AI Video App Maker
Artificial General Intelligence
Ai and higher level Artificial General Intelligence (AGI)
Artificial General Intelligence
Ai and higher level Artificial General Intelligence (AGI)
Faceswap AI Online
Swap Faces Video, Photo & GIFs Instantly with Powerful AI Tools - Faceswap AI Online FREE
Faceswap AI Online
Swap Faces Video, Photo & GIFs Instantly with Powerful AI Tools - Faceswap AI Online FREE
Faceswap AI Online
Swap Faces Video, Photo & GIFs Instantly with Powerful AI Tools - Faceswap AI Online FREE
Powerful AI Presentation PPT Maker for FREE
Build an impressive presentation with our free online AI presentation app
Your next top AI Assistant
Claude AI, developed by Anthropic
Your next top AI Assistant
Claude AI, developed by Anthropic
Temu Free $500 for New Users
Claim Free Temu $500 Credit via Affiliate & Influencer Program
Free TikTok Ads Credit
Master TikTok Ads for Your Business Marketing
Free TikTok Ads Credit
Master TikTok Ads for Your Business Marketing
Dall-E-OpenAI.com
Generate creative images automatically with AI
chatGPT4.win
Talk to ChatGPT by your mother language
First AI Product from Elon Musk - Grok/UN.com
Speak to Grok AI Chatbot with Your Language
Tooly.win
Open tool hub for free to use by any one for every one with hundreds of tools
GateIO.gomymobi.com
Free Airdrops to Claim, Share Up to $150,000 per Project
iPhoneKer.com
Save up to 630$ when buy new iPhone 16
Buy Tesla Optimus Robot
Order Your Tesla Bot: Optimus Gen 2 Robot Today for less than $20k
Cool Domains for Sale!
Author:
Previews:
Comment:
Votes:
Sent:
Size:
Rank:
Nate Haug [more]
53,128
0
0
0
32.75 KBytes
0 votes / 53,128 previews / 0 comment
02/06/2010
This JavaScript article lists some comparisons between two popular web programming languages in the world of open source...JavaScript and PHP - Comparisons to Learn - JavaScript and PHP - Comparisons to Learn
