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php constructor supports different number of parameter methods
Principle: Use in __construct func_num_args Get the number of parameters, and then execute different calls based on the number of parameters. The parameter value is obtained using the func_get_arg() method.
demo:
<?php class demo{ private $_args; public function __construct(){ $args_num = func_num_args(); // 获取参数个数 // 判断参数个数与类型 if($args_num==2){ $this->_args = array( 'id' => func_get_arg(0), 'dname' => func_get_arg(1) ); }elseif($args_num==1 && is_array(func_get_arg(0))){ $this->_args = array( 'device'=>func_get_arg(0) ); }else{ exit('func param not match'); } } public function show(){ echo '<pre class="brush:php;toolbar:false">'; print_r($this->_args); echo ''; } } // demo1 $id = 1; $dname = 'fdipzone'; $obj = new demo($id, $dname); $obj->show(); // demo2 $device = array('iOS','Android'); $obj = new demo($device); $obj->show(); ?>
Output after demo execution:
Array ( [id] => 1 [dname] => fdipzone ) Array ( [device] => Array ( [0] => iOS [1] => Android ) )
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