Home >Backend Development >PHP Problem >What are the implementation methods of PHP chain operation?

What are the implementation methods of PHP chain operation?

青灯夜游
青灯夜游Original
2021-05-28 17:36:222430browse

How to implement chain operation in php: 1. Use magic function "__call" combined with "call_user_func" to implement; 2. Use magic function "__call" combined with "call_user_func_array" to implement; 3. Use trim() function to implement.

What are the implementation methods of PHP chain operation?

The operating environment of this tutorial: windows7 system, PHP7.1 version, DELL G3 computer

There are many strings in php Function, for example, you need to filter the spaces at the end of a string first, and then find its length. The general way of writing is:

strlen(trim($str))

If you want to implement a chain operation similar to that in js, for example, how should you write it like the following

$str->trim()->strlen()

The following are implemented in three ways:

Method 1. Use the magic function __call combined with call_user_func to achieve

Thoughts:First define a string class StringHelper, the constructor assigns value directly, then calls the trim() and strlen() functions in a chain, and uses call_user_func in the called magic function __call() to handle the calling relationship. The implementation is as follows:

<?php
class StringHelper 
{
  private $value;
  function __construct($value)
  {
    $this->value = $value;
  }
  function __call($function, $args){
    $this->value = call_user_func($function, $this->value, $args[0]);
    return $this;
  }
  function strlen() {
    return strlen($this->value);
  }
}
$str = new StringHelper(" sd f 0");
echo $str->trim(&#39;0&#39;)->strlen();

Terminal execution script:

php test.php 
8

Method 2, use magic function __call combined with call_user_func_array to achieve

<?php
class StringHelper 
{
  private $value;
  function __construct($value)
  {
    $this->value = $value;
  }
  function __call($function, $args){
    array_unshift($args, $this->value);
    $this->value = call_user_func_array($function, $args);
    return $this;
  }
  function strlen() {
    return strlen($this->value);
  }
}
$str = new StringHelper(" sd f 0");
echo $str->trim(&#39;0&#39;)->strlen();

Instructions:

array_unshift(array,value1,value2,value3...)

array_unshift() Function is used to insert new elements into an array. The values ​​of the new array will be inserted at the beginning of the array.

call_user_func() and call_user_func_array are both methods of dynamically calling functions. The difference lies in the way parameters are passed.

Method three, do not use the magic function __call, use the trim() function to achieve

Just need to modify _call() to trim()Function is enough:

public function trim($t)
{
  $this->value = trim($this->value, $t);
  return $this;
}

The point is to return the $this pointer to facilitate calling the latter function.

Recommended learning: "PHP Video Tutorial"

The above is the detailed content of What are the implementation methods of PHP chain operation?. For more information, please follow other related articles on the PHP Chinese website!

Statement:
The content of this article is voluntarily contributed by netizens, and the copyright belongs to the original author. This site does not assume corresponding legal responsibility. If you find any content suspected of plagiarism or infringement, please contact admin@php.cn