PHP tags and embedding in HTML

Introduction

PHP tags let you write PHP code inside an HTML file. This helps make web pages that can change and show different things.

You want to show the current date or time on a webpage.

You need to display different messages based on user actions.

You want to include data from a database inside a webpage.

You want to mix HTML layout with PHP logic in one file.

Syntax

PHP

<?php
  // PHP code here
?>

The <?php ?> tags tell the server to run the code inside as PHP.

You can put PHP code anywhere inside an HTML file between these tags.

Examples

This example shows PHP code inside HTML that prints a message.

PHP

<html>
<body>
  <?php echo "Hello, world!"; ?>
</body>
</html>

PHP code inside a paragraph tag prints the current date.

PHP

<p>Today is <?php echo date('Y-m-d'); ?>.</p>

PHP sets a variable, then HTML uses PHP to show it inside a heading.

PHP

<?php
  $name = "Alice";
?>
<h1>Welcome, <?php echo $name; ?>!</h1>

Sample Program

This webpage uses PHP tags inside HTML to show the current year and a greeting based on the time.

PHP

<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>PHP Tags Example</title>
</head>
<body>
  <h1>My Webpage</h1>
  <p>Current year is <?php echo date('Y'); ?>.</p>
  <?php
    $hour = date('H');
    if ($hour < 12) {
      echo "<p>Good morning!</p>";
    } else {
      echo "<p>Good afternoon!</p>";
    }
  ?>
</body>
</html>

Important Notes

Always start PHP code with <?php and end with ?>.

PHP code runs on the server before the page shows in the browser.

You can switch between HTML and PHP as many times as you want in one file.

Summary

PHP tags let you add PHP code inside HTML files.

Use <?php ?> to start and end PHP code.

This helps make webpages that can change content dynamically.

Practice

1. Which of the following is the correct way to start a PHP code block inside an HTML file?

easy

A. <?php>

B. <?php

C. <php?

D. <?php/>

Solution

1. Step 1: Recognize PHP opening tag syntax

   The correct PHP opening tag is <?php without the closing > inside the tag itself.

2. Step 2: Compare options with correct syntax

   <?php matches the correct opening tag exactly, while others have extra characters or wrong order.

3. Final Answer:

   <?php -> Option B

4. Quick Check:

   PHP code starts with <?php [OK]

Hint: PHP code always starts with <?php [OK]

Common Mistakes:

• Using <php? instead of <?php
• Adding extra > inside the opening tag
• Confusing closing tag with opening tag

2. Which of these is the correct way to embed PHP code inside an HTML file?

easy

A. <?php echo 'Hello'; ?>

B. <php echo 'Hello'; ?>

C. <? echo 'Hello'; ?>

D. <?php echo 'Hello' ?>

Solution

1. Step 1: Identify correct PHP tags and syntax

   The full PHP opening tag is <?php and must be closed with ?>. The statement ends with a semicolon.

2. Step 2: Check each option for syntax correctness

   <?php echo 'Hello'; ?> uses <?php and closes with ?> and has a semicolon after echo statement, which is correct.

3. Final Answer:

   <?php echo 'Hello'; ?> -> Option A

4. Quick Check:

   Full PHP tags with semicolon = correct syntax [OK]

Hint: Use full <?php ... ?> tags with semicolon [OK]

Common Mistakes:

• Omitting semicolon after PHP statements
• Using <php instead of <?php
• Using short tags <? without php (may be disabled)

3. What will be the output of this code snippet embedded in an HTML file?

<html>
<body>
<?php
  echo "Today is ".date('l').".";
?>
</body>
</html>

medium

A. Today is Monday.

B. Today is l.

C. Today is date('l').

D. Syntax error

Solution

1. Step 1: Understand PHP date function usage

   The date('l') function returns the full name of the current day of the week, e.g., Monday, Tuesday.

2. Step 2: Analyze echo statement output

   The echo concatenates "Today is " with the day name and a period, so output will be like "Today is Monday." depending on the current day.

3. Final Answer:

   Today is Monday. -> Option A

4. Quick Check:

   date('l') returns day name, so output is Today is Monday. [OK]

Hint: date('l') returns day name, output shows full sentence [OK]

Common Mistakes:

• Treating date('l') as a string literal
• Missing concatenation operator
• Expecting syntax error from correct code

4. Identify the error in this PHP embedded in HTML code:

<html>
<body>
<?php
  echo "Hello World"
?>
</body>
</html>

medium

A. Echo statement syntax error

B. Incorrect PHP opening tag

C. Missing semicolon after echo statement

D. Missing closing PHP tag

Solution

1. Step 1: Check PHP statement syntax

   The echo statement must end with a semicolon ; to separate statements.

2. Step 2: Verify PHP tags and code completeness

   The opening tag <?php and closing tag ?> are correct and present.

3. Final Answer:

   Missing semicolon after echo statement -> Option C

4. Quick Check:

   Statements need semicolon; missing here causes error [OK]

Hint: Always end PHP statements with semicolon [OK]

Common Mistakes:

• Forgetting semicolon after echo
• Confusing short tags with full tags
• Assuming closing tag is optional

5. You want to embed PHP in HTML to display a greeting that changes based on the time of day. Which code snippet correctly uses PHP tags and logic inside HTML?

hard

A. <?php echo if (date('H') < 12) { 'Good morning!'; } else { 'Good afternoon!'; } ?>

B. <? if (date('H') < 12) echo 'Good morning!'; else echo 'Good afternoon!'; ?>

C. <php if (date('H') < 12) { echo 'Good morning!'; } else { echo 'Good afternoon!'; } ?>

D. <?php if (date('H') < 12) { echo 'Good morning!'; } else { echo 'Good afternoon!'; } ?>

Solution

1. Step 1: Check PHP opening and closing tags

   <?php if (date('H') < 12) { echo 'Good morning!'; } else { echo 'Good afternoon!'; } ?> uses full <?php ... ?> tags correctly. <? if (date('H') < 12) echo 'Good morning!'; else echo 'Good afternoon!'; ?> uses short tags which may be disabled. <php if (date('H') < 12) { echo 'Good morning!'; } else { echo 'Good afternoon!'; } ?> uses <php which is invalid. <?php echo if (date('H') < 12) { 'Good morning!'; } else { 'Good afternoon!'; } ?> misuses echo with if statement.

2. Step 2: Verify PHP syntax and logic

   <?php if (date('H') < 12) { echo 'Good morning!'; } else { echo 'Good afternoon!'; } ?> correctly uses if-else with echo inside braces. <?php echo if (date('H') < 12) { 'Good morning!'; } else { 'Good afternoon!'; } ?> tries to echo an if statement directly, which is invalid syntax.

3. Final Answer:

   <?php if (date('H') < 12) { echo 'Good morning!'; } else { echo 'Good afternoon!'; } ?> -> Option D

4. Quick Check:

   Full PHP tags + proper if-else syntax = correct [OK]

Hint: Use full <?php tags and proper if-else syntax [OK]

Common Mistakes:

• Using short tags <? which may be disabled
• Incorrect PHP opening tag like <php
• Trying to echo an if statement directly