注意：未定义的索引：第11行的C：\ xampp \ htdocs \ dbconnectioncheck.php中的txt_image

Question

为什么它给出错误？任何想法

if(isset($_POST['submit']))
{
     $obj_image->image_name=str_replace("'","''",$_POST['txt_image_name']);
     $obj_image->image=str_replace("'","''",$_POST['txt_image']);//line 11
     $obj_image->insert_into_image();
}