What front-end developers need to know about PHP

As a front-end developer, it is very necessary to understand PHP. Although PHP is a back-end development language, mastering a certain amount of PHP knowledge can help front-end developers better understand the entire web development process, improve work efficiency, and collaborate better with back-end developers. In this article, we will discuss some PHP-related knowledge that front-end developers need to know and provide specific code examples.

What is PHP?

PHP (Hypertext Preprocessor) is a server-side scripting language used to develop dynamic web pages. It can be mixed with HTML code, embedded in HTML, and works with various databases. One of PHP's biggest advantages is its open source nature and its widespread use in web development.

PHP basic syntax

1. Variables: In PHP, variables start with the $ symbol, such as $ name = "John";. Variables do not need to declare their type before use.

   $name = "John";
   echo $name;

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2. Conditional statements: Conditional statements in PHP are similar to the syntax in JavaScript.

   $age = 25;
   if ($age >= 18) {
       echo "成年人";
   } else {
       echo "未成年人";
   }

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3. Loop statements: Loop statements in PHP include for, while, foreachwait.

   for($i = 0; $i < 5; $i++) {
       echo $i;
   }

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The combination of PHP and front-end development

1. Interaction with JavaScript: Front-end developers can interact with back-end developers through AJAX technology End-to-end interaction enables asynchronous loading of data.

   var xhr = new XMLHttpRequest();
   xhr.open("GET", "backend.php", true);
   xhr.send();
   xhr.onreadystatechange = function() {
       if (xhr.readyState == XMLHttpRequest.DONE) {
           if (xhr.status == 200) {
               console.log(xhr.responseText);
           }
       }
   }

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   $data = array("name" => "Alice", "age" => 30);
   echo json_encode($data);

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2. Form processing: PHP can receive the data submitted by the form and process it.

   <form action="process.php" method="post">
       <input type="text" name="username">
       <input type="password" name="password">
       <button type="submit">Submit</button>
   </form>

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   $username = $_POST["username"];
   $password = $_POST["password"];
   echo "用户名：" . $username . "<br>";
   echo "密码：" . $password;

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3. Session Management: PHP can manage the user's login status through Session to improve the security of the website.

   session_start();
   $_SESSION['username'] = 'Alice';

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   session_start();
   echo $_SESSION['username'];

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Summary

Through the above introduction, we have learned some PHP-related knowledge that front-end developers need to know, including basic syntax, integration with front-end development, etc. Mastering a certain amount of PHP knowledge can help front-end developers better understand the entire web development process and collaborate better with back-end developers. I hope the above content is helpful to front-end developers.

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