PHP中的多重选择 - 如何编辑数据？

Question

it is easy to create a form that will allow a user to select multiple values and then get the data that was entered. What I want to know is how to recreate that form based on the information in the database? ie Edit the data.

<form action="<?=$_SERVER['PHP_SELF']?>" method="post">
<select name="test[]" multiple="multiple">
    <option value="one">one</option>
    <option value="two">two</option>
    <option value="three">three</option>
    <option value="four">four</option>
    <option value="five">five</option>
</select>
<input type="submit" value="Send" />
</form>

<?php
    $test=$_POST['test'];
    if ($test){
     foreach ($test as $t){echo 'You selected ',$t,'<br />';}
    }
?>

Say values two and foru were seleted in the original data. How would I recreate the form to edit the data like the code below:

<form action="<?=$_SERVER['PHP_SELF']?>" method="post">
<select name="test[]" multiple="multiple">
    <option value="one">one</option>
    <option selected value="two">two</option>
    <option value="three">three</option>
    <option selected value="four">four</option>
    <option value="five">five</option>
</select>
<input type="submit" value="Send" />
</form>

Initially I want the code for add and edit to work. Eventually I want to be able to enter various multiple select options in a form and to edit them.

Answer 1

The easiest way to handle that is to store valid form values in an array.

$hourList = range(1, 24);

Then iterate over the array when printing

foreach($hourList as $hour)
{
  if ($hour == $enteredValue)
  {
    echo "<option selected value=\"{$hour}\">{$hour}</option>";
  }else
  {
    echo "<option value=\"{$hour}\">{$hour}</option>";
  }
}

If you're accepting multiple selections you may want to look into in_array() rather than direct comparison. For situations where you're offering a 'Every Month/day/year' option, simply prepend that to the array after using range.