php asynchronous execution method

In PHP development, some codes take a long time to complete, which may affect user experience and website performance. At this time, asynchronous execution becomes very important.

What is asynchronous execution?

Asynchronous execution refers to allowing code to execute in the background while the program is running. That is to say, while waiting for the code execution result, the program is allowed to continue executing other codes.

In PHP, there are two main methods of asynchronous execution: multi-threading and asynchronous non-blocking.

Multi-threading refers to starting multiple threads in a program, and each thread can perform different tasks at the same time. Asynchronous non-blocking means that the code does not wait for another piece of code to complete execution, but performs other operations during execution, similar to the form of a callback function.

Let’s introduce these two asynchronous execution methods respectively.

Using multi-threading to implement asynchronous execution

PHP does not have built-in multi-threading support, but it can be implemented through extensions. Common extensions include pthreads and parle. Here we take the pthreads extension as an example.

First you need to make sure that PHP on the server has the pthreads extension installed. You can confirm by running the following command in the terminal:

php -m | grep -i pthreads

If pthreads is displayed, it means the installation has been successful.

Next, you can use the following code to implement multi-threaded asynchronous execution:

class MyThread extends Thread {
    public function run() {
        // 执行需要异步执行的代码
    }
}

// 创建一个线程对象
$thread = new MyThread();

// 启动线程，异步执行代码
$thread->start();

// 执行其他代码，但不会等待 $thread 的执行结果

Use asynchronous non-blocking to implement asynchronous execution

In addition to multi-threading, you can also use asynchronous non-blocking way to achieve asynchronous execution. This method is more lightweight than multi-threading, but requires mastering some asynchronous programming concepts and techniques.

In PHP 7, there is built-in support for asynchronous non-blocking programming, which can be implemented using the following code:

$handle = fopen("path/to/file", "rb");

stream_set_blocking($handle, 0);

while (!feof($handle)) {
    // 非阻塞读取文件
    fread($handle, 8192);
    // 继续执行其他代码
    // ...
}

It is worth noting that using asynchronous non-blocking methods to implement asynchronous execution may cause Code readability is reduced, and some more complex tasks may require the use of multi-threading or other forms of asynchronous execution.

Summary

Asynchronous execution is particularly important in PHP development, which can reduce code time and improve program performance and user experience. We introduced two methods to implement asynchronous execution, namely multi-threading and asynchronous non-blocking. In actual development, it is necessary to choose an appropriate method to implement asynchronous execution according to the specific situation.

The above is the detailed content of php asynchronous execution method. For more information, please follow other related articles on the PHP Chinese website!