Podcast
Podcast
Podcast
Something went wrong
Questions and Answers
Questions and Answers
Which PHP superglobal is used to collect form data sent via the HTTP POST method?
Which PHP superglobal is used to collect form data sent via the HTTP POST method?
- $_REQUEST
- $_SESSION
- $_POST (correct)
- $_GET
The HTTP GET method is suitable for transmitting sensitive information such as passwords.
The HTTP GET method is suitable for transmitting sensitive information such as passwords.
False (B)
What is the approximate character limit for data sent using the HTTP GET method?
What is the approximate character limit for data sent using the HTTP GET method?
2000
The ______ attribute in an HTML form specifies the URL to which the form data will be sent.
The ______ attribute in an HTML form specifies the URL to which the form data will be sent.
Match each term with its correct description:
Match each term with its correct description:
Why is the htmlspecialchars() function important when processing form data?
Why is the htmlspecialchars() function important when processing form data?
The stripslashes() function should always be used to sanitize user input, regardless of the context.
The stripslashes() function should always be used to sanitize user input, regardless of the context.
What is the purpose of the trim() function in the context of form data processing?
What is the purpose of the trim() function in the context of form data processing?
Cross-Site Scripting (XSS) attacks involve injecting ______ into web pages viewed by other users.
Cross-Site Scripting (XSS) attacks involve injecting ______ into web pages viewed by other users.
Match the function with its corresponding task in form validation:
Match the function with its corresponding task in form validation:
In an HTML form, which method is generally preferred for sending sensitive data?
In an HTML form, which method is generally preferred for sending sensitive data?
Superglobals like $_GET and $_POST are only accessible within the function where they are first defined.
Superglobals like $_GET and $_POST are only accessible within the function where they are first defined.
What type of vulnerability is addressed by escaping HTML characters in form inputs?
What type of vulnerability is addressed by escaping HTML characters in form inputs?
The ______ function can be used to remove backslashes from a string, which might be necessary if magic quotes are enabled.
The ______ function can be used to remove backslashes from a string, which might be necessary if magic quotes are enabled.
Match each URL component with its description:
Match each URL component with its description:
What is the primary purpose of form validation?
What is the primary purpose of form validation?
Using $_SERVER['PHP_SELF'] in the form action attribute is always a secure practice.
Using $_SERVER['PHP_SELF'] in the form action attribute is always a secure practice.
What does the term 'superglobal' mean in the context of PHP variables?
What does the term 'superglobal' mean in the context of PHP variables?
When using the GET method, the parameters are passed to the resource via the ______ part of the URL.
When using the GET method, the parameters are passed to the resource via the ______ part of the URL.
Match the potential security risk with its mitigation strategy:
Match the potential security risk with its mitigation strategy:
Which function is used to validate if a string is a valid email address in PHP?
Which function is used to validate if a string is a valid email address in PHP?
The POST method allows users to bookmark pages with pre-filled form data.
The POST method allows users to bookmark pages with pre-filled form data.
What is the primary difference between how GET and POST methods transmit data?
What is the primary difference between how GET and POST methods transmit data?
In a URL, the part that specifies parameters passed to a resource is called the ______.
In a URL, the part that specifies parameters passed to a resource is called the ______.
Match the HTML input type with its intended purpose:
Match the HTML input type with its intended purpose:
Why should 'GET' not be used to send passwords?
Why should 'GET' not be used to send passwords?
The htmlspecialchars() function is used to prevent form validation, ensuring that no input is rejected.
The htmlspecialchars() function is used to prevent form validation, ensuring that no input is rejected.
State the security reason developers encode user input using functions like htmlspecialchars() rather than allowing direct HTML rendering.
State the security reason developers encode user input using functions like htmlspecialchars() rather than allowing direct HTML rendering.
A security attack that injects client-side script into web pages viewed is known as a ______ attack.
A security attack that injects client-side script into web pages viewed is known as a ______ attack.
Match the methods to the descriptions accordingly :
Match the methods to the descriptions accordingly :
Questions and Answers
Something went wrong
Flashcards
Flashcards
$_GET and $_POST
$_GET and $_POST
Superglobals used in PHP to collect form data.
HTML form action attribute
HTML form action attribute
Specifies where the form data is sent for processing.
HTML form method attribute
HTML form method attribute
Specifies the HTTP method used to send the form data.
GET
GET
Signup and view all the flashcards
URL format
URL format
Signup and view all the flashcards
POST
POST
Signup and view all the flashcards
$_GET and $_POST superglobals
$_GET and $_POST superglobals
Signup and view all the flashcards
$_SERVER["PHP_SELF"]
$_SERVER["PHP_SELF"]
Signup and view all the flashcards
htmlspecialchars()
htmlspecialchars()
Signup and view all the flashcards
Cross-site scripting (XSS)
Cross-site scripting (XSS)
Signup and view all the flashcards
trim() function
trim() function
Signup and view all the flashcards
stripslashes() function
stripslashes() function
Signup and view all the flashcards
test_input() function
test_input() function
Signup and view all the flashcards
Flashcards
Something went wrong
Study Notes
Study Notes
PHP and Form Handling
- PHP superglobals
$_GETand$_POSTare used to collect form data
Simple HTML Form
- The HTML form includes two input fields and a submit button
Form explanation
action="welcome.php": specifies where the form data is sent upon submissionmethod="post": uses the HTTP POST method for sending form data, which is safer for sensitive information like emailsname="name"is the field for the user's namename="email"is the field for the user's email address- The submit button sends the data to the server
Processing Form Data
- After the user submits the form, the data is processed by "welcome.php" using the HTTP POST method
Displaying Submitted Data
- Submitted data displayed by echoing the values of the variables
Welcome.php Explanation
- The name and email input sent via the POST method
$_POST["name"]retrieves the user's name input$_POST["email"]retrieves the user's email input
HTTP GET Method
- The same result can be achieved using the HTTP GET method
Welcome_get.php
- To display the results using get, you need to use the
$_Getcommand instead of$_POST
When to Use GET
- Information sent using the GET method is visible in the URL
- GET has a limit of about 2000 characters for the amount of information sent
- GET is suitable for sending non-sensitive data and allows bookmarking
- The GET method should never be used for sending passwords or sensitive data
Format of URL
- scheme://hostname:port/path?query#fragment
- scheme: The protocol used (e.g., http, https, ftp)
- hostname: The domain name or IP address (e.g., example.com)
- port (optional): The port number (e.g., :80, :443)
- path (optional): The specific location on the server (e.g., /products)
- query (optional): Parameters passed to the resource (e.g., ?id=123)
- fragment (optional): A section within the page (e.g., #top)
- Example:
https://www.example.com:443/products/item?id=123#reviews
When to Use POST
- Information sent via POST is invisible and embedded in the HTTP request body with no limits on the amount of data
- POST does not allow bookmarking
GET vs POST
- Both GET and POST create an array of key/value pairs
keysare the names of form controlsvaluesare the input data- Both GET and POST are treated as superglobals
$_GETand$_POST, accessible regardless of scope
PHP Form Validation
- Proper validation is crucial to protect forms from hackers
Form Validation Example
- The form validation includes fields for Name, E-mail, Website, Comment, and Gender, with specified validation rules
Validation Rules
- Name: Required field containing letters and whitespace only
- E-mail: Required field containing a valid email address
- Website: Optional field that must contain a valid URL if present
- Comment: Optional multi-line input field (textarea)
- Gender: Required field with one option selected
HTML Code: Text Fields
- Name, email, and website fields use text input elements while the comment field uses a textarea element
HTML Code: Radio Buttons
- Gender fields are implemented using radio buttons
Form Element
- The form data is sent with
method="post"upon submission
$_SERVER["PHP_SELF"] Variable
$_SERVER["PHP_SELF"]returns the filename of the currently executing script, and submits the form data to the same pagehtmlspecialchars()converts special characters into HTML entities to prevent Cross-site Scripting (XSS) attacks
Form Element Warning
- The
$_SERVER["PHP_SELF"]variable can be exploited by hackers - entering a slash "/" can allow Cross Site Scripting (XSS) commands to execute
Example of XSS Attack
- Example of what could happen without
htmlspecialchars(): - User submits:
<input type="text" name="name" value="<b>John</b>"> - Without
htmlspecialchars()it will display John in bold - With
htmlspecialchars()it will display<b>John</b>as text
HTML Escaped Code
<converts to<>converts to>&converts to&"converts to"'converts to'
Cross-site scripting (XSS)
- A computer security vulnerability in web applications allowing attackers to inject client-side scripts into web pages viewed by users
Exploiting PHP_SELF
- It is possible to input javascript inside the tag, which will execute
Validating With PHP
- Pass all variables through PHP's
htmlspecialchars()function - This prevents the execution of injected scripts by saving them as HTML escaped code
Additional Validation Steps
- Use
trim()to strip unnecessary characters andstripslashes()to remove backslashes from user input - Create a function such as
test_input()to handle the validation process
Test_input() Function
- Trims data using
trim($data) - Removes backslashes using
stripslashes($data) - Converts special characters using
htmlspecialchars($data)
Expanded Validation
- Check if required fields are empty and assign an error message if they are
- Use
filter_varwithFILTER_VALIDATE_EMAILfilters to validate email format - Validate websites using
preg_matchand a regular expression to check if a valid URL
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Study Notes
Something went wrong
