Lesson 5.2. HTML forms, POST or GET?

Syntax

When creating an HTML form, there are two methods for transmitting the data entered by the user, the GET and POST method which respectively transmit the data in the navigation bar and in the HTTP request.

The GET method

The default method is the GET method. The data will be visible in the URL, for example:

/processing.php?firstname=Pierre&lastname=Dupont

The processing PHP page will receive data in a variable (an array) named $_GET.

Some remarks and precautions:

• The length of URLs can be limited (about 2048 characters).
• Never use the GET method to transmit sensitive data.
• The user can add the treatment page to his favorites.ns ses favoris.

Syntax

<form action="process.php" method="get">
  <!-- Form fields -->
</form>

The POST method

With the POST method, the form data is transmitted in the HTTP request. If the site uses an SSL certificate (domain starting with https instead of http), data will be encrypted. This method is more secure.

The processing page will receive data in the variable $ _POST.

• Use this method for transmiting sensitive data.
• The user will not be able to add the treatment page to his favorites.

Syntax

<form action="process.php" method="post">
  <!-- Form fields -->
</form>

Exercice

Modify the script in the following example so that the data is transmitted with the GET method. Check the URL of the processing page after form is submitted.

See also

• Web development class
• Lesson 1.1. History of the Internet
• Lesson 1.2 Introduction to HTML
• Lesson 1.3. Special characters in HTML
• Lesson 1.4. Comments in HTML
• Lesson 1.5. Global structure of HTML pages
• Lesson 1.6. Hyperlinks in HTML
• Lesson 1.7. ID attribute in HTML tags
• Lesson 1.8. HTML anchors
• Lesson 1.9. Images in HTML pages
• Lesson 1.10. HTML tables
• Lesson 1.11. Most used HTML tags
• Lesson 1.12. Some advice
• Lesson 1.13. Ressources
• Lesson 2.1. Introduction to CSS
• Lesson 2.2. Inline CSS
• Lesson 2.3. Internal CSS
• Lesson 2.4. External CSS
• Lesson 2.5. CSS selectors
• Lesson 2.6. CSS colors
• Lesson 2.7. Margin and padding
• Lesson 2.8. CSS units
• Lesson 2.9. Most used CSS properties
• Lesson 3.1. History of JavaScript
• Lesson 3.2. JavaScript Hello World
• Lesson 3.3. Console.log
• Lesson 3.4. Comments in JavaScript
• Lesson 3.5. Variables in JavaScript
• Lesson 3.6. JavaScript events
• Lesson 3.7. Document Object Model (DOM)
• Lesson 3.8. Changing HTML
• Lesson 3.8. JavaScript frameworks
• Lesson 4.1. Introduction to PHP
• Lesson 4.2. PHP tags
• Lesson 4.3. PHP variables
• Lesson 4.4. isset vs empty vs is_null
• Lesson 4.5. PHP operators
• Lesson 4.6. PHP quotes
• Lesson 4.7. Tests in PHP: if .. else
• Lesson 4.8. PHP arrays
• Lesson 4.9. PHP loops
• Lesson 4.10. PHP sessions
• Lesson 5.1. HTML forms
• Lesson 5.3. Input fields
• Lesson 5.4. HTML form fields
• Lesson 6.1. Introduction to MySQL
• Lesson 6.2. phpMyAdmin
• Lesson 6.3. SQL queries
• Lesson 6.4. Connect to MySQL in PHP
• Lesson 6.5. SQL queries in PHP
• Lesson 6.6. Getting data from MySQL in PHP
• Lesson 6.7. Get last ID

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