Concat在for循环中的值域上进行变换而不显示结果

Question

I have this page:

<?php
for($i=1; $i<=3; $i++){
  $until_he.$i = htmlentities($_POST['until'.$i])
}
?>

<form action="" method...>
<?php
  for($i=1; $i<=3; $i++){
       ...
       print '<input name="until'.$i.'" id="until'.$i.'" class="textinput" value="'.$until_he.$i.'" type="date" min="'.date("Y-m-d").'"/>';
       ...
  }
?>
...

Now:

$until_he

has content only once the form is posted, otherwise it's empty. On the other hand

$i

is already defined. So as I load the page I get values 1, 2, 3 on the fields.

I'd like to get values on the files only once the user post the forum. As I load the page the fields should be empty.

Thank you

Answer 1

Try this:

<?php
for($i=1; $i<=3; $i++){
   $until_he.$i = htmlentities($_POST['until'.$i]);
   $fieldValue = (trim($until_he.$i)==$i)?"":$until_he;
   ...     
   print '<input name="until'.$i.'" 
                 id="until'.$i.'" 
                 class="textinput" 
                 value="'.$fieldValue.'" 
                 type="date" min="'.date("Y-m-d").'"/>';
   ...
}
?>