NavigationProblem with POST

Spanito

This is the results page2 I use to output data collected from page1 (a form page). (this code I got originally from a post here)
I modified it to work on my site. If I don't include the $_POST variable it works great on displaying all records. But I want to allow users to POST from a form their criteria.

Below is code that works great if I don't use the $_POST variable, my problem is a user will use a form to POST the information to this page2, The first page shows me the first record correctly, and tells me how many records. example Page 1 of 133,, but when I try to navigate to the next page I get this error:

Notice: Trying to get property of non-object in C:\Program Files\Apache Group\Apache2\htdocs\www\website\searchallhousetype.php on line 93

and so on for all the other objects....

I'm thinking that that I'm doing something wrong with the $_POST.

Here is the code listed below:

<?
include("dbviewplansinfo.inc.php");
mysql_connect("localhost",$username,$password);
@mysql_select_db($database) or die( "Unable to select database");

// change the database information as needed or

// use your own connection method

// database connection variables

// next two functions are to set up our navigation
function previousPage() {
global $prev;
if ($prev == 0) {
echo " ";
}
else {
echo "<a href=\"$_SERVER[PHP_SELF]?page=$prev\">Previous</a>";
}
}

function nextPage() {
global $next;
global $num_rows;
if ($next <= $num_rows) {
echo "<a href=\"$_SERVER[PHP_SELF]?page=$next\">Next</a>";
}
else {
echo " ";
}
}

// The following statement sets the various variables
// used to navigate our database
if (isset($GET['page'])) {
$page = $GET['page'];
$prev = $page - 1;
$current = $page;
$next = $page + 1;
$limit = $prev;
}
else {
$prev = 0;
$current = 1;
$next = 2;
$limit = $prev;
}

// We need to see just how many entries there are in the table
// don't forget to change index_test to your own table
$num_rows = mysql_result(mysql_query("SELECT COUNT(*) FROM houseplans Where housetype = '".$_POST['housetype']."'"),0);

// Now we fetch the information from the db, using the LIMIT
// function of the sql statement to only fetch the single row we want.
// What the $limit variable is set to above is where the pointer
// will start in the table, this is called the offset. The next
// number limits the number of rows returned, in this case we only
// want one.
$query = "SELECT plan, housetype, sqft, bedrooms, garage, bathrooms, houseimage, sqftarea FROM houseplans Where housetype = '".$_POST['housetype']."' LIMIT $limit, 1";
$result = mysql_query($query);

// I like to turn the information into objects for handling
$row = mysql_fetch_object($result);

// Now we output the information in a meaningful way,
// note the use of the previousPage and nextPage functions
?>

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
<HTML>
<HEAD>
<TITLE>Hodder Construction Ltd. - View Plans</TITLE>
<META http-equiv=Content-Type content="text/html; charset=iso-8859-1">
</HEAD>
<BODY BACKGROUND="images/contactinpic.gif">

<table width="90%" align="center" cellpadding="3" cellspacing="3" border="1">
<tr>

<td colspan="6" align="center"><a href="index2.html"><IMG SRC="images/home.gif"></a><a href="AboutUs.html"><IMG SRC="images/ourcompany.jpg"></a><a href="sales.html"><IMG SRC="images/sales.jpg"></a><a href="Renovations.html"><IMG SRC="images/renovations.jpg"></a><a href="ClientsResidential.html"><IMG SRC="images/clients.jpg"></a><a href="ContactInfo.html"><IMG SRC="images/contactus.jpg"></a></td>

</tr>

<tr>
<td align="center">Plan</td>
<td align="center">House Type</td>
<td align="center">Square Feet</td>
<td align="center">Bedrooms</td>
<td align="center">Bathrooms</td>
<td align="center">Garages</td>
</tr>
<tr>
<td align="center"><? echo stripslashes($row->plan); ?></td>
<td align="center"><? echo stripslashes($row->housetype); ?></td>
<td align="center"><? echo stripslashes($row->sqft); ?></td>
<td align="center"><? echo stripslashes($row->bedrooms); ?></td>
<td align="center"><? echo stripslashes($row->bathrooms); ?></td>
<td align="center"><? echo stripslashes($row->garage); ?></td>
</tr>
<tr>
<td align="center"><? previousPage(); ?> </td>
<td colspan="4" align="center"><? echo $current. " of " .$num_rows; ?></td>
<td align="center"> <? nextPage(); ?></td>
</tr>
<tr>
<td colspan="6" align="center"><IMG SRC="plansimages/<? echo stripslashes($row->houseimage); ?>"></TD>

<tr>
<td align="center"><? previousPage(); ?> </td>
<td colspan="4" align="center"><? echo $current. " of " .$num_rows; ?></td>
<td align="center"> <? nextPage(); ?></td>
</tr>
<tr>
<td align="center"><IMG SRC="images/logosmall.gif"></td>
<td colspan="4" align="center">For pricing, or more information on this plan, please click on the below link <A HREF="mailto:info@hodder.ca?subject=More info on Plan <? echo stripslashes($row->plan); ?>">info@hodder.ca</A></td>
<td align="center"><IMG SRC="images/logosmall.gif"></td>
</tr>
<tr>

<td colspan="6" align="center"><a href="index2.html"><IMG SRC="images/home.gif"></a><a href="AboutUs.html"><IMG SRC="images/ourcompany.jpg"></a><a href="sales.html"><IMG SRC="images/sales.jpg"></a><a href="Renovations.html"><IMG SRC="images/renovations.jpg"></a><a href="ClientsResidential.html"><IMG SRC="images/clients.jpg"></a><a href="ContactInfo.html"><IMG SRC="images/contactus.jpg"></a></td>

</tr>

</table>
</BODY>
</HTML>
<?
// close the database connection
mysql_close();
?>

Any help on steering me in the right direction would be greatly appreciated.

ozzythaman

dear friend, the problem is the following:

when users press the submit button from the first page everything is fine because $_POST[] is set for those variables.

when you then press a next page button the $_POST variables from the first page will dissappear.

the main problem is that you are mixing both POST and GET variables, which causes confusion here.

_GET variables are the variables appended to the URL like:
?a=123&b=777&c=152

but POST variables must be sent explicitly by a SUBMIT button with all the variables embedded as form fields or hidden fields (check out hidden fields, you WILL need them sometime).

and since there is no POST submission (ONLY GET via the URL) when pressing the "next" link all the POST variables will dissappear as said.

what you should do is use METHOD=GET in the first form and
when creating the next write this:

<a href=\"$_SERVER[PHP_SELF]?page=$next&var1fromsubmit=$var1fromsubmit&var2fromsubmit=$var2fromsubmit\">Next</a>";

so all variables will be passed on to all other pages (AS _GET VARS!)

note: the submit button can be used for both POST and GET submission (POST-invisible & GET-appended to the URL),
but you HAVE to use a submission button for POST submission.

note2: if you use a POST submission from page1 to page2, you will be asked if you want to resend all form data every time you reload page 2...
AND you can not give a direct link to any search page when using POST. only GET variables can be saved in a bookmark!
all searchengines use GET variables when searching..

my main rule is use GET for everything except when submitting passwords, you dont want to have them seen in the URL...

that will get you going..