How to combine several dropdown list values in mysql query? - php

Question

<form method="post" action="search.php">
<select name="Num[]">
<option value="">Select One</option>
<option value="numofpeople">Number of people</option>
</select>
<select name="op[]">
<option value="">Select One</option>
<option value=">4">>4</option>
<option value=">2">>2</option>
</select>
<br />
<select name="num2[]">
<option value="">Select One</option>
<option value="price">Price</option>
</select>
<select name="op2[]">
<option value="">Select One</option>
<option value="<20000"><20000</option>
<option value="<40000"><40000</option>
</select>
<br />
<div class="input-group-btn">
<button class="btn btn-default" type="submit"><i class="glyphicon glyphicon-search"></i></button>
</div>
</form>
Here is my code to provide a dropdown list for the user. It will act as a filter to generate more specific result through mysql and don't get the logic to combine these dropdown values.
I would like to have something like:
Select * from hotel where price < 40000;
and I will provide all keywords after "Where".

Answer 1

Select boxes name are defined as array in html and your requirement is a user can select a single option in a select box. So you need to update the name of select boxes. You no need to add < in select box values, These conditions used at server end. I have corrected the HTML.
<form method="post" action="">
<select name="Num">
<option value="">Select One</option>
<option value="numofpeople">Number of people</option>
</select>
<select name="op">
<option value="">Select One</option>
<option value="4">>4</option>
<option value="2">>2</option>
</select>
<br />
<select name="num2">
<option value="">Select One</option>
<option value="price">Price</option>
</select>
<select name="op2">
<option value="">Select One</option>
<option value="20000"><20000</option>
<option value="40000"><40000</option>
</select>
<br />
<div class="input-group-btn">
<button class="btn btn-default" type="submit" name="search_btn"><i class="glyphicon glyphicon-search"></i> Search</button>
</div>
</form>
Server Side code for handle selected values and add to query.
if(isset($_POST['search_btn'])){
$conditons = array();
if(isset($_POST['Num'])){
$conditons[] = '`people` = "'.$_POST['Num'].'"';
}
if(isset($_POST['op'])){
$conditons[] = '`option` < '.$_POST['op'];
}
if(isset($_POST['price'])){
$conditons[] = '`price` = '.$_POST['price'];
}
if(isset($_POST['op2'])){
$conditons[] = '`op2` < '.$_POST['op2'];
}
$conditons = implode(' & ', $conditons);
echo $query = 'select * from hotel where '.$conditons;
}
You an update your real field name in conditions. After added conditions, result query will be as -
select * from hotel where `people` = "numofpeople" & `option` < 4 & `op2` < 20000

Answer 2

Here is a very generic example that I just put together. This code is not tested, but I have written like this before.
<?php
// Checks to see if post variables are available
if(isset($_POST)) {
// Creates original command
$query = "SELECT * FROM hotel WHERE "
// gets each value from the post
foreach($_POST as $key => $value) {
$query .= $key . "=" . $value . "AND ";
}
// Removes the trailing "AND "
$query = substr($query, 0, -4);
echo $query;
}
If you need to switch things up depending on key, you can just do a switch inside of the foreach statement that will check the key value. The key is the "name" attr that is assigned in the HTML that you are posting from.
This method is also not sanitized because I did not get a response to which connection type you are using, but it shouldn't be that hard. If you need me to write it, then I would be more than happy to do so.