Added Perl, PHP.
This commit is contained in:
parent
b80f78b411
commit
608673cb2b
|
|
@ -0,0 +1,454 @@
|
|||
# PHP Cheat Sheet
|
||||
|
||||
## Table of Contents
|
||||
|
||||
1. [Variables](#variables)
|
||||
2. [Data Types](#data-types)
|
||||
3. [Operators](#operators)
|
||||
4. [Control Structures](#control-structures)
|
||||
5. [Functions](#functions)
|
||||
6. [Arrays](#arrays)
|
||||
7. [Strings](#strings)
|
||||
8. [File Handling](#file-handling)
|
||||
9. [Error Handling](#error-handling)
|
||||
10. [Classes and Objects](#classes-and-objects)
|
||||
11. [Sessions and Cookies](#sessions-and-cookies)
|
||||
12. [Database Connectivity](#database-connectivity)
|
||||
13. [Regular Expressions](#regular-expressions)
|
||||
|
||||
## Variables
|
||||
|
||||
### Declaration and Assignment
|
||||
```php
|
||||
<?php
|
||||
$variable_name = value;
|
||||
?>
|
||||
```
|
||||
|
||||
### Variable Types
|
||||
- String: `$string_variable = "Hello";`
|
||||
- Integer: `$int_variable = 42;`
|
||||
- Float: `$float_variable = 3.14;`
|
||||
- Boolean: `$bool_variable = true;`
|
||||
|
||||
## Data Types
|
||||
|
||||
### Scalar Types
|
||||
- String
|
||||
- Integer
|
||||
- Float (double)
|
||||
- Boolean
|
||||
|
||||
### Compound Types
|
||||
- Array
|
||||
- Object
|
||||
|
||||
### Special Types
|
||||
- Resource
|
||||
- NULL
|
||||
|
||||
## Operators
|
||||
|
||||
### Arithmetic Operators
|
||||
```php
|
||||
+, -, *, /, %, ** (exponentiation)
|
||||
```
|
||||
|
||||
### Comparison Operators
|
||||
```php
|
||||
==, ===, !=, !==, <, >, <=, >=
|
||||
```
|
||||
|
||||
### Logical Operators
|
||||
```php
|
||||
&& (and), || (or), ! (not)
|
||||
```
|
||||
|
||||
### Assignment Operators
|
||||
```php
|
||||
=, +=, -=, *=, /=, %=
|
||||
```
|
||||
|
||||
## Control Structures
|
||||
|
||||
### If Statement
|
||||
```php
|
||||
if (condition) {
|
||||
// code to be executed if the condition is true
|
||||
} elseif (another_condition) {
|
||||
// code to be executed if the previous condition was false and this one is true
|
||||
} else {
|
||||
// code to be executed if all conditions are false
|
||||
}
|
||||
```
|
||||
|
||||
### Switch Statement
|
||||
```php
|
||||
switch (variable) {
|
||||
case value1:
|
||||
// code to be executed if variable equals value1
|
||||
break;
|
||||
case value2:
|
||||
// code to be executed if variable equals value2
|
||||
break;
|
||||
default:
|
||||
// code to be executed if variable doesn't match any case
|
||||
}
|
||||
```
|
||||
|
||||
### Loops
|
||||
#### For Loop
|
||||
```php
|
||||
for ($i = 0; $i < 5; $i++) {
|
||||
// code to be executed in each iteration
|
||||
}
|
||||
```
|
||||
|
||||
#### While Loop
|
||||
```php
|
||||
while (condition) {
|
||||
// code to be executed as long as the condition is true
|
||||
}
|
||||
```
|
||||
|
||||
#### Do-While Loop
|
||||
```php
|
||||
do {
|
||||
// code to be executed at least once, then repeated as long as the condition is true
|
||||
} while (condition);
|
||||
```
|
||||
|
||||
## Functions
|
||||
|
||||
### Function Declaration
|
||||
```php
|
||||
function functionName($param1, $param2) {
|
||||
// code to be executed
|
||||
return $result; // optional
|
||||
}
|
||||
```
|
||||
|
||||
### Function Call
|
||||
```php
|
||||
$result = functionName($arg1, $arg2);
|
||||
```
|
||||
|
||||
## Arrays
|
||||
|
||||
### Indexed Array
|
||||
```php
|
||||
$indexed_array = array("value1", "value2", "value3");
|
||||
```
|
||||
|
||||
### Associative Array
|
||||
```php
|
||||
$assoc_array = array("key1" => "value1", "key2" => "value2");
|
||||
```
|
||||
|
||||
### Multidimensional Array
|
||||
```php
|
||||
$multi_array = array(
|
||||
array("value1", "value2"),
|
||||
array("value3", "value4")
|
||||
);
|
||||
```
|
||||
|
||||
## Strings
|
||||
|
||||
### Concatenation
|
||||
```php
|
||||
$string1 = "Hello";
|
||||
$string2 = "World";
|
||||
$concatenated = $string1 . " " . $string2;
|
||||
```
|
||||
|
||||
### String Functions
|
||||
```php
|
||||
strlen($string); // length of the string
|
||||
strpos($string, "find"); // position of the first occurrence of "find"
|
||||
substr($string, start, length); // extract a portion of the string
|
||||
```
|
||||
|
||||
## File Handling
|
||||
|
||||
### Reading from a File
|
||||
```php
|
||||
$file_content = file_get_contents("filename.txt");
|
||||
```
|
||||
|
||||
### Writing to a File
|
||||
```php
|
||||
file_put_contents("filename.txt", "Hello, World!");
|
||||
```
|
||||
|
||||
## Error Handling
|
||||
|
||||
### Try-Catch Block
|
||||
```php
|
||||
try {
|
||||
// code that may throw an exception
|
||||
} catch (Exception $e) {
|
||||
// handle the exception
|
||||
echo "Error: " . $e->getMessage();
|
||||
}
|
||||
```
|
||||
|
||||
## Classes and Objects
|
||||
|
||||
### Class Declaration
|
||||
```php
|
||||
class MyClass {
|
||||
// properties and methods
|
||||
}
|
||||
```
|
||||
|
||||
### Object Instantiation
|
||||
```php
|
||||
$object = new MyClass();
|
||||
```
|
||||
|
||||
## Sessions and Cookies
|
||||
|
||||
### Sessions
|
||||
```php
|
||||
session_start();
|
||||
$_SESSION['username'] = 'John';
|
||||
```
|
||||
|
||||
### Cookies
|
||||
```php
|
||||
setcookie('user', 'Jane', time() + 3600, '/');
|
||||
```
|
||||
|
||||
## Database Connectivity
|
||||
|
||||
### MySQLi Connection
|
||||
```php
|
||||
$servername = "localhost";
|
||||
$username = "username";
|
||||
$password = "password";
|
||||
$dbname = "database";
|
||||
|
||||
$conn = new mysqli($servername, $username, $password, $dbname);
|
||||
```
|
||||
|
||||
### MySQLi Query
|
||||
```php
|
||||
$sql = "SELECT * FROM table";
|
||||
$result = $conn->query($sql);
|
||||
```
|
||||
|
||||
## Regular Expressions
|
||||
|
||||
### Pattern Matching
|
||||
```php
|
||||
$pattern = "/[0-9]+/";
|
||||
$string = "There are 123 apples";
|
||||
preg_match($pattern, $string, $matches);
|
||||
```
|
||||
|
||||
```
|
||||
# PHP Extended Examples
|
||||
|
||||
## Variables
|
||||
|
||||
### Variable Scope
|
||||
```php
|
||||
<?php
|
||||
$global_variable = "I am global";
|
||||
|
||||
function myFunction() {
|
||||
$local_variable = "I am local";
|
||||
echo $local_variable; // Accessible within the function
|
||||
echo $global_variable; // Accessing a global variable requires the global keyword
|
||||
}
|
||||
|
||||
myFunction();
|
||||
echo $global_variable; // Accessible outside the function
|
||||
// echo $local_variable; // This will throw an error since $local_variable is not in scope
|
||||
?>
|
||||
```
|
||||
|
||||
## Control Structures
|
||||
|
||||
### Foreach Loop with Arrays
|
||||
```php
|
||||
<?php
|
||||
$colors = array("Red", "Green", "Blue");
|
||||
|
||||
foreach ($colors as $color) {
|
||||
echo $color . "\n";
|
||||
}
|
||||
?>
|
||||
```
|
||||
|
||||
### Switch Statement with Fall-Through
|
||||
```php
|
||||
<?php
|
||||
$day = "Monday";
|
||||
|
||||
switch ($day) {
|
||||
case "Monday":
|
||||
case "Tuesday":
|
||||
echo "It's a weekday.";
|
||||
break;
|
||||
case "Saturday":
|
||||
case "Sunday":
|
||||
echo "It's the weekend.";
|
||||
break;
|
||||
default:
|
||||
echo "Not a valid day.";
|
||||
}
|
||||
?>
|
||||
```
|
||||
|
||||
## Functions
|
||||
|
||||
### Default Parameter Values
|
||||
```php
|
||||
<?php
|
||||
function greet($name = "Guest") {
|
||||
echo "Hello, " . $name . "!";
|
||||
}
|
||||
|
||||
greet(); // Outputs: Hello, Guest!
|
||||
greet("John"); // Outputs: Hello, John!
|
||||
?>
|
||||
```
|
||||
|
||||
### Variable Number of Arguments
|
||||
```php
|
||||
<?php
|
||||
function sum(...$numbers) {
|
||||
$result = 0;
|
||||
foreach ($numbers as $number) {
|
||||
$result += $number;
|
||||
}
|
||||
return $result;
|
||||
}
|
||||
|
||||
echo sum(1, 2, 3, 4); // Outputs: 10
|
||||
?>
|
||||
```
|
||||
|
||||
## Arrays
|
||||
|
||||
### Array Functions
|
||||
```php
|
||||
<?php
|
||||
$numbers = array(1, 2, 3, 4, 5);
|
||||
|
||||
// Count elements in an array
|
||||
echo count($numbers); // Outputs: 5
|
||||
|
||||
// Find the sum of array elements
|
||||
echo array_sum($numbers); // Outputs: 15
|
||||
|
||||
// Merge two arrays
|
||||
$moreNumbers = array(6, 7, 8);
|
||||
$combined = array_merge($numbers, $moreNumbers);
|
||||
print_r($combined); // Outputs: Array ( [0] => 1 [1] => 2 [2] => 3 [3] => 4 [4] => 5 [5] => 6 [6] => 7 [7] => 8 )
|
||||
?>
|
||||
```
|
||||
|
||||
## Strings
|
||||
|
||||
### Regular Expression Match and Replace
|
||||
```php
|
||||
<?php
|
||||
$string = "The quick brown fox jumps over the lazy dog";
|
||||
|
||||
// Check if the string contains the word "fox"
|
||||
if (preg_match("/fox/", $string)) {
|
||||
echo "Found a fox!";
|
||||
}
|
||||
|
||||
// Replace "fox" with "cat"
|
||||
$newString = preg_replace("/fox/", "cat", $string);
|
||||
echo $newString; // Outputs: The quick brown cat jumps over the lazy dog
|
||||
?>
|
||||
```
|
||||
|
||||
## File Handling
|
||||
|
||||
### Reading and Writing to Files
|
||||
```php
|
||||
<?php
|
||||
// Reading from a file
|
||||
$file_content = file_get_contents("example.txt");
|
||||
echo $file_content;
|
||||
|
||||
// Writing to a file
|
||||
$new_content = "This is some new content.";
|
||||
file_put_contents("example.txt", $new_content);
|
||||
?>
|
||||
```
|
||||
|
||||
## Classes and Objects
|
||||
|
||||
### Class Inheritance
|
||||
```php
|
||||
<?php
|
||||
class Animal {
|
||||
public $name;
|
||||
|
||||
public function __construct($name) {
|
||||
$this->name = $name;
|
||||
}
|
||||
|
||||
public function makeSound() {
|
||||
echo "Generic animal sound\n";
|
||||
}
|
||||
}
|
||||
|
||||
class Dog extends Animal {
|
||||
public function makeSound() {
|
||||
echo "Woof!\n";
|
||||
}
|
||||
}
|
||||
|
||||
$dog = new Dog("Buddy");
|
||||
echo $dog->name; // Outputs: Buddy
|
||||
$dog->makeSound(); // Outputs: Woof!
|
||||
?>
|
||||
```
|
||||
|
||||
## Database Connectivity
|
||||
|
||||
### MySQLi Prepared Statements
|
||||
```php
|
||||
<?php
|
||||
$servername = "localhost";
|
||||
$username = "username";
|
||||
$password = "password";
|
||||
$dbname = "database";
|
||||
|
||||
// Create connection
|
||||
$conn = new mysqli($servername, $username, $password, $dbname);
|
||||
|
||||
// Check connection
|
||||
if ($conn->connect_error) {
|
||||
die("Connection failed: " . $conn->connect_error);
|
||||
}
|
||||
|
||||
// Prepared statement
|
||||
$sql = "SELECT * FROM users WHERE username = ?";
|
||||
$stmt = $conn->prepare($sql);
|
||||
$username = "john_doe";
|
||||
$stmt->bind_param("s", $username);
|
||||
$stmt->execute();
|
||||
|
||||
// Fetch result
|
||||
$result = $stmt->get_result();
|
||||
while ($row = $result->fetch_assoc()) {
|
||||
print_r($row);
|
||||
}
|
||||
|
||||
// Close connection
|
||||
$stmt->close();
|
||||
$conn->close();
|
||||
?>
|
||||
```
|
||||
|
||||
```
|
||||
|
||||
|
|
@ -1,8 +1,13 @@
|
|||
# cheetsheetz
|
||||
# CheetSheetz
|
||||
|
||||
Collection of various technical "cheat sheets".
|
||||
|
||||
[Markdown](https://git.namenode.xyz/CSnap/cheetsheetz/src/branch/main/markdown.md)
|
||||
|
||||
[Perl](https://git.namenode.xyz/CSnap/cheetsheetz/src/branch/main/perl.md)
|
||||
|
||||
[PHP]((https://git.namenode.xyz/CSnap/cheetsheetz/src/branch/main/PHP.md)
|
||||
|
||||
[Python](https://git.namenode.xyz/CSnap/cheetsheetz/src/branch/main/python.md)
|
||||
|
||||
[LEMP Guide](https://git.namenode.xyz/CSnap/cheetsheetz/src/branch/main/LEMP.md)
|
||||
|
|
|
|||
|
|
@ -0,0 +1,280 @@
|
|||
# Perl Cheat Sheet
|
||||
|
||||
## Basics
|
||||
|
||||
### Comments
|
||||
```perl
|
||||
# This is a comment
|
||||
```
|
||||
|
||||
### Print
|
||||
```perl
|
||||
print "Hello, World!\n";
|
||||
```
|
||||
|
||||
### Variables
|
||||
```perl
|
||||
$scalar_variable = 42;
|
||||
@array_variable = (1, 2, 3);
|
||||
%hash_variable = ('key' => 'value');
|
||||
```
|
||||
|
||||
## Control Structures
|
||||
|
||||
### if-else
|
||||
```perl
|
||||
if ($condition) {
|
||||
# Code to execute if condition is true
|
||||
} else {
|
||||
# Code to execute if condition is false
|
||||
}
|
||||
```
|
||||
|
||||
### foreach
|
||||
```perl
|
||||
foreach $item (@array) {
|
||||
# Code to execute for each item in the array
|
||||
}
|
||||
```
|
||||
|
||||
### while
|
||||
```perl
|
||||
while ($condition) {
|
||||
# Code to execute while condition is true
|
||||
}
|
||||
```
|
||||
|
||||
## Subroutines
|
||||
|
||||
```perl
|
||||
sub greet {
|
||||
my $name = shift;
|
||||
print "Hello, $name!\n";
|
||||
}
|
||||
|
||||
greet("Alice");
|
||||
```
|
||||
|
||||
## Regular Expressions
|
||||
|
||||
### Matching
|
||||
```perl
|
||||
if ($string =~ /pattern/) {
|
||||
# Code to execute if pattern is found in $string
|
||||
}
|
||||
```
|
||||
|
||||
### Substitution
|
||||
```perl
|
||||
$string =~ s/find/replace/;
|
||||
```
|
||||
|
||||
## File Handling
|
||||
|
||||
### Open and Read
|
||||
```perl
|
||||
open(my $file, '<', 'filename.txt') or die "Can't open file: $!";
|
||||
while (<$file>) {
|
||||
chomp;
|
||||
print "$_\n";
|
||||
}
|
||||
close($file);
|
||||
```
|
||||
|
||||
### Open and Write
|
||||
```perl
|
||||
open(my $file, '>', 'output.txt') or die "Can't open file: $!";
|
||||
print $file "Hello, File!\n";
|
||||
close($file);
|
||||
```
|
||||
|
||||
## Modules
|
||||
|
||||
### Using Modules
|
||||
```perl
|
||||
use Module::Name;
|
||||
```
|
||||
|
||||
### Exporting Functions
|
||||
```perl
|
||||
use Module::Name qw(function1 function2);
|
||||
```
|
||||
|
||||
## References
|
||||
|
||||
### Scalar Reference
|
||||
```perl
|
||||
$scalar_ref = \$scalar_variable;
|
||||
```
|
||||
|
||||
### Array Reference
|
||||
```perl
|
||||
$array_ref = \@array_variable;
|
||||
```
|
||||
|
||||
### Hash Reference
|
||||
```perl
|
||||
$hash_ref = \%hash_variable;
|
||||
```
|
||||
|
||||
# Advanced Perl Cheat Sheet
|
||||
|
||||
## Basics
|
||||
|
||||
### Comments
|
||||
```perl
|
||||
# This is a comment
|
||||
```
|
||||
|
||||
### Print
|
||||
```perl
|
||||
print "Hello, World!\n";
|
||||
```
|
||||
|
||||
### Variables
|
||||
```perl
|
||||
$scalar_variable = 42;
|
||||
@array_variable = (1, 2, 3);
|
||||
%hash_variable = ('key' => 'value');
|
||||
```
|
||||
|
||||
### Data Types
|
||||
```perl
|
||||
$string = "Perl";
|
||||
$number = 42;
|
||||
$float = 3.14;
|
||||
```
|
||||
|
||||
## Control Structures
|
||||
|
||||
### if-else
|
||||
```perl
|
||||
if ($condition) {
|
||||
# Code to execute if condition is true
|
||||
} elsif ($another_condition) {
|
||||
# Code to execute if another condition is true
|
||||
} else {
|
||||
# Code to execute if all conditions are false
|
||||
}
|
||||
```
|
||||
|
||||
### foreach
|
||||
```perl
|
||||
foreach $item (@array) {
|
||||
# Code to execute for each item in the array
|
||||
}
|
||||
```
|
||||
|
||||
### while
|
||||
```perl
|
||||
while ($condition) {
|
||||
# Code to execute while condition is true
|
||||
}
|
||||
```
|
||||
|
||||
## Subroutines
|
||||
|
||||
```perl
|
||||
sub greet {
|
||||
my $name = shift;
|
||||
print "Hello, $name!\n";
|
||||
}
|
||||
|
||||
greet("Alice");
|
||||
```
|
||||
|
||||
### Returning Values
|
||||
```perl
|
||||
sub add {
|
||||
my ($num1, $num2) = @_;
|
||||
return $num1 + $num2;
|
||||
}
|
||||
|
||||
my $result = add(3, 4);
|
||||
print "Sum: $result\n";
|
||||
```
|
||||
|
||||
## Regular Expressions
|
||||
|
||||
### Matching
|
||||
```perl
|
||||
if ($string =~ /pattern/) {
|
||||
# Code to execute if pattern is found in $string
|
||||
}
|
||||
```
|
||||
|
||||
### Substitution
|
||||
```perl
|
||||
$string =~ s/find/replace/;
|
||||
```
|
||||
|
||||
## File Handling
|
||||
|
||||
### Open and Read
|
||||
```perl
|
||||
open(my $file, '<', 'filename.txt') or die "Can't open file: $!";
|
||||
while (<$file>) {
|
||||
chomp;
|
||||
print "$_\n";
|
||||
}
|
||||
close($file);
|
||||
```
|
||||
|
||||
### Open and Write
|
||||
```perl
|
||||
open(my $file, '>', 'output.txt') or die "Can't open file: $!";
|
||||
print $file "Hello, File!\n";
|
||||
close($file);
|
||||
```
|
||||
|
||||
## Modules
|
||||
|
||||
### Using Modules
|
||||
```perl
|
||||
use Module::Name;
|
||||
```
|
||||
|
||||
### Exporting Functions
|
||||
```perl
|
||||
use Module::Name qw(function1 function2);
|
||||
```
|
||||
|
||||
## References
|
||||
|
||||
### Scalar Reference
|
||||
```perl
|
||||
$scalar_ref = \$scalar_variable;
|
||||
```
|
||||
|
||||
### Array Reference
|
||||
```perl
|
||||
$array_ref = \@array_variable;
|
||||
```
|
||||
|
||||
### Hash Reference
|
||||
```perl
|
||||
$hash_ref = \%hash_variable;
|
||||
```
|
||||
|
||||
## Structuring a Perl Script for Bash
|
||||
|
||||
### Create a Perl Script
|
||||
```perl
|
||||
#!/usr/bin/perl
|
||||
use strict;
|
||||
use warnings;
|
||||
|
||||
# Perl script code here
|
||||
print "Hello from Perl!\n";
|
||||
```
|
||||
|
||||
### Make it Executable
|
||||
```bash
|
||||
chmod +x script.pl
|
||||
```
|
||||
|
||||
### Run from Bash
|
||||
```bash
|
||||
./script.pl
|
||||
```
|
||||
|
||||
Loading…
Reference in New Issue