When you declare one variable, the initial type is null, but the type can be changed by assign statement.
global $my_var;
echo gettype($my_var);
$my_var = new stdClass();
$my_var->name = 'test';
$my_var->city = 'china';
//$my_var['weather']= 'cold';
echo gettype($my_var);
var_dump($my_var);
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http://www.bkjia.com/PHPjc/735900.htmlwww.bkjia.comtruehttp://www.bkjia.com/PHPjc/735900.htmlTechArticleWhen you declare one variable, the initial type is null, but the type can be changed by assign statement. global $my_var;echo gettype($my_var);$my_var = new stdClass();$my_var->nam...
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