From 608673cb2b388667a0d68b2e4ec9d9863f661659 Mon Sep 17 00:00:00 2001
From: CSnap <clarence@namenode.xyz>
Date: Sun, 19 Nov 2023 04:05:23 +0000
Subject: [PATCH] Added Perl, PHP.

---
 PHP.md    | 454 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
 README.md |   7 +-
 perl.md   | 280 +++++++++++++++++++++++++++++++++
 3 files changed, 740 insertions(+), 1 deletion(-)
 create mode 100644 PHP.md
 create mode 100644 perl.md

diff --git a/PHP.md b/PHP.md
new file mode 100644
index 0000000..1370955
--- /dev/null
+++ b/PHP.md
@@ -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();
+?>
+```
+
+```
+
diff --git a/README.md b/README.md
index fa99518..cec484a 100644
--- a/README.md
+++ b/README.md
@@ -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)
diff --git a/perl.md b/perl.md
new file mode 100644
index 0000000..ac77883
--- /dev/null
+++ b/perl.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
+```
+