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
)
)This article introduces how the PHP constructor supports different numbers of parameters. For more related content, please pay attention to the PHP Chinese website.
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