MYSQL SELECT with user selected OPTION values

Question

I am trying to filter out a MYSQL table according to user selected values in my php file list.php

My table users have field stdYr , in which elements have values of S00, S01, ... S40 .

in html body, I have this chunk of code:

<form method="post" role="form" action="list.php">
    <div>
        <select multiple>
            <option value="all">Select</option>
            <option value="S00">74</option>
            <option value="S01">75</option>
            <option value="S02">76</option>
            ...
            <option value="S40">114/option>
        </select>
        <button type="submit"></button>

    </div>
</form>

And then, I want to select those with selected stdYr values. The approach I could come up with is passing the values of option through $_POST :

if(isset($_POST['S00']) || isset($_POST['S11']) || ...
    ... || isset($_POST['S40'])) {
    /*some code to get only those set values*/
    $query="SELECT * FROM users WHERE stdYR = '/*some stuff*/'";
}

But with different possible selections of values, I couldn't figure out how exactly to do this... And even with the solution, I see this approach very repetitive and silly. How am I supposed to deal with such things?

I greatly appreciate your help! Thanks :D

Answer 1

Your form is incorrect. Your select MUST have a name attribute for it to get submitted to the server.

<select name="options[]" multiple>
        ^^^^^^^^^^^^^^^
   <option ...>
   ...
</select>

Note the [] on the name field. That'll tell PHP to accept multiple values, making $_POST['options'] an array itself. Then it's a simple matter of:

foreach($_POST['options'] as $option) {
     insert_into_db($option);
}

Answer 2

Use this way:

<form method="post" role="form" action="list.php">
 <div>
    <select name="MyOptions[]" multiple>
        <option value="all">Select</option>
        <option value="S00">74</option>
        <option value="S01">75</option>
        <option value="S02">76</option>
        ...
        <option value="S40">114/option>
    </select>
    <button type="submit"></button>

  </div>
</form>

 print '<pre>';
 print_r($_POST);
 $selectOption = $_POST['MyOptions']; //get post result and then work as you wish

Answer 3

You could try this :

<select name="stdYR[]" multiple>

<?php
$stdYR = $_POST['stdYR'];
$stdYR_ct = count($stdYR);
$i=0;
while($i < $stdYR_ct){
    $stdYR_SQL .= "'$stdYR[$i]',";
    $i++;
}
if (preg_grep("/All/i", $stdYR) or ($stdYR_ct < 1)){
    $stdYR_SQL = "";
}else{
    $stdYR_SQL = eregi_replace(",$",'',$stdYR_SQL);
    $stdYR_SQL = " AND stdYR IN($stdYR_SQL)";
}

$query = "SELECT * FROM users WHERE 1=1 $stdYR_SQL ";
?>