Running Your First PHP Script

To run the first PHP script, you must first build a server environment, and then write basic code to test and run. 1. Locally install integrated environments such as XAMPP, WAMP or MAMP; 2. Use PHP that comes with Mac or Linux system; 3. Run code through an online PHP editor; 4. Place the PHP file in the server directory such as htdocs; 5. Write a .php file containing <?php echo "Hello, world!"; ?>; 6. Visit http://localhost/test/index.php through the browser to view the results; 7. Pay attention to check whether the server is running, whether the path is correct and whether the syntax is wrong; 8. You can try to output time or process forms and deepen your understanding.

It is actually not difficult to run your first PHP script. As long as the environment is well set and the writing method is correct, you can quickly see the effect. PHP is a server-side language, so you cannot open it directly in the browser like HTML or JavaScript. You need a server environment that supports PHP.

Ready to run the environment

To run PHP scripts, you must first make sure you have an environment that can execute PHP. Common methods are:

• Local installation of XAMPP, WAMP or MAMP : These toolkits integrate Apache, MySQL and PHP, making them suitable for beginners to quickly build environments.
• Use the PHP (Mac or Linux) that comes with the system : Some systems have PHP pre-installed. You can enter php -v through the terminal to see if it is installed.
• Online PHP editor : such as 3v4l.org or onlinephp.io, such websites can run PHP code directly without configuring the local environment.

After the installation is completed, it is recommended to place the PHP file in the server directory, such as the htdocs folder of XAMPP, so that it will be correctly parsed when accessed through the browser.

Write a simple PHP file

Create a new file with .php suffix, such as index.php , and then write the most basic code in it:

 <?php
echo "Hello, world!";
?>

A few points to note:

• The start tag <?php and end tags ?> cannot be omitted (although the end tag can be omitted in pure PHP files, it is recommended for beginners to keep it).
• echo is the keyword of the output content, followed by a string or variable.
• Each statement ends with a semicolon.

After saving, put this file in the server directory, such as http: htdocs/test/index.php , and then visit http://localhost/test/index.php in the browser to see the output Hello, world!.

FAQs and debugging tips

Sometimes, you clearly wrote the correct code but you can't see the expected results. This may be due to the following reasons:

• Not accessed through the server : it is not possible to open the .php file directly by double-clicking, it must be accessed through a method similar to http://localhost/xxx .
• The server is not started : If you are using XAMPP or WAMP, you must start the Apache service first.
• There is a syntax error in the code : you can add ini_set('display_errors', 1); to the top of the PHP file to make the server display the error message.
• File encoding or path problems : Try to name files and paths in English to avoid parsing failures in Chinese or special characters.

If the page is blank and does not output, check the above points first, basically all the problems can be located.

Try adding some small functions

After you can run the first script smoothly, you can try adding a little function, such as outputting the current time:

 <?php
echo "The current time is: " . date("Ymd H:i:s");
?>

Or make a simple form processing:

 <?php
if ($_SERVER["REQUEST_METHOD"] == "POST") {
    $name = $_POST["name"];
    echo "Hello," . htmlspecialchars($name);
}
?>

<form method="post">
    <input type="text" name="name">
    <input type="submit" value="submit">
</form>

These small examples can help you understand PHP's running mechanism faster.

Basically that's all, running the first PHP script doesn't require too many steps, but some details are easy to ignore. As long as the environment is good, writing a simple script will run quite quickly.

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