php在多个输入搜索表单上返回空白页

Question

I am brand new to php/mysql and brand new to the site, so thanks ahead for any help. I need to create a php script which will return results from a search form with four input fields. It needs to be so that any combination of the fields can be searched or none at all which will return all of the items from the database. As of now, all that is being returned when I click submit on the form page is a blank page.

This is what I have so far. I tried it as one query intially which tried to capture all of the requirements, and then as a series of "if" statements, which I read to do on this site, but all I get is a blank page.

<?php
if (isset(
  $_POST['product_description'],$_POST['product_finish'],
  $_POST ['product_minimum_price'], $_POST['product_maximum_price'])) {

    $product_description = ($_POST['product_description']);
    $product_finish = ($_POST['product_finish']);
    $product_minimum_price = ($_POST['product_minimum_price']);
    $product_maximum_price = ($_POST['product_maximum_price']);

    $query = "SELECT ProductDescription, ProductFinish, ProductStandardPrice FROM product_t";
    if (isset($_POST['product_description'])) {
        $query = "SELECT ProductDescription, ProductFinish, ProductStandardPrice
             FROM product_t
             WHERE ProductDescription LIKE '%.$product_description.%'";
    }

    if (isset($_POST['product_finish'])) {
        $query = "SELECT ProductDescription, ProductFinish, ProductStandardPrice
             FROM product_t
             WHERE ProductDescription LIKE '%.$product_finish.%'";
    }

    if (isset($_POST['product_minimum_price'])) {
        $query = "SELECT ProductDescription, ProductFinish, ProductStandardPrice
             FROM product_t
             WHERE ProductStandardPrice >= 'product_minimum_price'";
    }

    if (isset($_POST['product_maximum_price'])) {
        $query = "SELECT ProductDescription, ProductFinish, ProductStandardPrice
             FROM product_t
             WHERE ProductStandardPrice <= 'product_maximum_price'";
    }

    $result = mysql_query($query);
    if($result === FALSE) die(mysql_error());

    echo '<table align="left" cellspacing="1" cellpadding ="5" border="1"><tr><td
    align="left">Product Description</td><td align="left">Product Finish</td><td align="left">
    Product Standard Price</td></tr>';

    while ($row=mysql_fetch_array($result, MYSQL_ASSOC)) {
        echo '<tr><td align="left">' .$row['ProductDescription'].
        '</td><td align="left">'.$row['ProductFinish'].
        '</td><td align="left">'.$row['ProductStandardPrice'].'</td></tr>';
    }

   echo '</table>';
   mysql_close();
}
?>

Answer 1

If you're getting a blank page it's because your outer if statement isn't evaluating to true. Include an else clause and echo something else.

Answer 2

Chances are you have a form name misspelled, you should have the page only echo those POST variables to double check you're getting data to them.

Also, you're missing the connection to the database, I suggest using PDO's as your database connection, you'll get much better error reporting.

mysql_connect("localhost", "mysql_user", "mysql_password") or
die("Could not connect: " . mysql_error());
mysql_select_db("mydb");

HTH