PHP syntax and structure are foundational aspects of writing PHP code. Understanding these basics is crucial for developing PHP applications effectively. Here’s a detailed explanation of PHP syntax and structure:

1. PHP Tags

PHP code is embedded within HTML using special PHP tags. The most common tag is <?php ... ?>.

• Standard PHP Tag:

  <?php
    // PHP code goes here
  ?>
  

• Short PHP Tag:

  <? 
    // Short form (must be enabled in php.ini)
  ?>
  

• Echo Short Tag:

  <?= "Hello, World!"; ?>
  

  • The <?= ... ?> tag is shorthand for <?php echo ... ?>.

2. Basic Syntax

PHP code typically involves statements that end with a semicolon (;). Code blocks are enclosed within curly braces {}.

• Variables:

  • Variables in PHP are declared with a dollar sign ($) followed by the variable name.

  <?php
    $variableName = "Hello, World!";
    echo $variableName;
  ?>
  

• Case Sensitivity:

  • PHP variable names are case-sensitive, but function and class names are not.

  <?php
    $variable = "Hello";
    $VARIABLE = "World";
    echo $variable; // Outputs: Hello
  ?>