PHP 7教程

Welcome to the PHP 7 tutorial! In this tutorial, we will cover everything you need to know about PHP 7.

What is PHP 7?

PHP 7 is the latest major release of the PHP programming language. It was released on December 3, 2015 and is considered a significant improvement over previous versions.

Features of PHP 7

PHP 7 comes with a number of new features and improvements, including:

• Improved performance: PHP 7 is significantly faster than previous versions of PHP, which means your web applications will run faster.

• Scalar type declarations: PHP 7 introduces scalar type declarations, which allow you to specify the type of a function's parameters and return value (e.g. int, string, bool).

• Return type declarations: PHP 7 also introduces return type declarations, which allow you to specify the type of a function's return value.

• Null coalescing operator: PHP 7 introduces the null coalescing operator (??), which allows you to check if a variable is set and not null, and if it's not, return a default value.

• Spaceship operator: PHP 7 introduces the spaceship operator (<=>), which allows you to compare two values and return -1, 0, or 1 depending on whether the left value is less than, equal to, or greater than the right value.

• Group use declarations: PHP 7 allows you to group multiple use declarations on the same line, which can make your code easier to read.

Getting started with PHP 7

To get started with PHP 7, you'll need to download and install it on your computer. You can download PHP 7 from the official PHP website (https://www.php.net/downloads.php).

Once you've installed PHP 7, you'll need to choose a text editor or IDE to write your PHP code. Some popular options include:

• Visual Studio Code
• Sublime Text
• Atom
• PhpStorm

Writing your first PHP 7 program

To write your first PHP 7 program, create a new file with the .php extension (e.g. myprogram.php) and add the following code:

<?php

echo "Hello, world!";

?>

Save the file and open it in your web browser. You should see the message "Hello, world!" displayed on the screen.

Conclusion

Congratulations! You've completed the PHP 7 tutorial. We hope you found it helpful and informative. If you have any questions or feedback, please let us know.