How to use PHP to develop a simple online survey function
In modern society, survey is one of the important means to obtain information and understand user needs. Using PHP to develop a simple and practical online survey function can help us quickly collect data and analyze the results. The following will introduce how to use PHP to implement this function and provide specific code examples.

1. Build the environment
First, you need to build a PHP development environment. You can use XAMPP, WAMP and other software, or install components such as Apache, PHP and MySQL by yourself.

2. Create a database
Create a database in MySQL to store relevant data of the questionnaire. Databases and tables can be created using tools such as phpMyAdmin.

3. Create a questionnaire form
Create a questionnaire form in the database to store the questions and options of the questionnaire. The table structure can be designed as follows:

CREATE TABLEquestionnaire(
idint(11) NOT NULL AUTO_INCREMENT,
questionvarchar(255) NOT NULL,
option1varchar(255) NOT NULL,
option2varchar(255) NOT NULL,
option3varchar(255) NOT NULL,
option4varchar(255) NOT NULL,
PRIMARY KEY (id)
) ENGINE=InnoDB DEFAULT CHARSET=utf8 ;

4. Write a questionnaire page
Create a questionnaire page where users can answer questions. You can use HTML and CSS to design the layout and style of the page, and use PHP to dynamically generate questions and options. The following is a sample code:

在线调查问卷
 
 {$row['question']}"; echo " {$row['option1']}
"; echo " {$row['option2']}
"; echo " {$row['option3']}
"; echo " {$row['option4']}

"; } ?>  

5. Processing submission data
Create a submit.php file to Process the answer results submitted by the user and save the results to the database. The following is sample code:

// Get answers submitted by users
$answers = array();
foreach ($_POST as $key => $value ) {

if (strpos($key, 'answer') !== false) { $answers[$key] = intval($value); }

}

// Save the answer to the database
$conn = mysqli_connect('localhost', 'root', 'password', 'database');
foreach ($answers as $questionId => $answer) {

$id = intval(str_replace('answer', '', $questionId)); $sql = "INSERT INTO answers (question_id, answer) VALUES ($id, $answer)"; mysqli_query($conn, $sql);

}

// Operation after successful submission, such as jumping to the result page or displaying success message
echo "Submission successful! Thank you for your participation!";
?>

In this way, a simple online survey function is completed. Users can fill in their answers on the questionnaire page and submit, and the submitted results will be saved in the database. We can further analyze and process this data as needed.

Summary
By using PHP to develop a simple online survey function, you can easily collect user feedback and needs, providing effective reference for business decisions and product improvements. The above code example is just a basic framework, and the page layout, question type and data processing can be expanded and optimized according to actual needs. I hope this article can help you understand and use PHP to develop online survey functions!