PHP - How to call multiple functions of a class on top of each other-CodePudding

How to create a class that can call multiple functions?

example:

class ClassName
{
    public static function func1()
    {
    }

    public static function func2()
    {
    }

    public static function func3()
    {
    }

}

ClassName::func1()->func2()->func3();

result Uncaught Error: Call to a member function funcX() on null

CodePudding user response：

This won't work at all with static methods as you suggest.

This is possible however with an instance object, that is called "builder pattern" or "fluid style":

<?php
class ClassName {
    public function func1(): ClassName {
      echo "1";
      return $this;
    }

    public function func2(): ClassName {
      echo "2";
      return $this;
    }

    public function func3(): ClassName {
      echo "3";
      return $this;
    }
}

(new ClassName())->func1()->func2()->func3();

The output is:

123

CodePudding user response：

In PHP you cannot call static functions "piggybacked" like you can in, say, JavaScript. You have a few options .. Call them in a list, one at a time .. Like so:

ClassName::func1();
ClassName::func2();
ClassName::func3();

Or Like

$foo = new ClassName;
$foo->func1();
$foo->func2();
$foo->func3();

Now if you want to run them all with a single call, you need to nest the functions BUT we have to rid ourselves of the static method ...

<?php

class ClassName
{
   public function func1()
   {
     echo "1 \n";
     $this->func2();
   }
   public function func2()
   {
     echo "2 \n";
     $this->func3();
   }
   public function func3()
   {
     echo "3 \n";
   }

}

$foo = new ClassName;
$foo->func1();

Finally, if you want to run all of your functions within a class sequentially, you can use get_class_methods and loop through all the functions ... IE

<?php

class ClassName
{
   public static function func1()
   {
      echo "1 \n";
   }
   public static function func2()
   {
      echo "2 \n";
   }
   public static function func3()
   {
      echo "3 \n";
   }
}

$functions = get_class_methods('Classname');

foreach ($functions as $function){
    ClassName::$function();
}

Both methods will result in:

1
2
3

If you choose to rid yourself of the static method however (as seen in our "nested function").. And you just choose public .. Then your syntax is possible using @arkascha's method of building out.

 public function func1(): ClassName { // From @arkascha's answer .. 

 $foo = new ClassName;
 $foo->func1()->func2()->func3();

The difference is understanding public method and static method