Losing data in an array after button submit

lon22

Hello, I having a problem with losing data in an array variable. The problem is that after I submit a query to a DB I fill an array with some values. This works fine, but after I do another submit with a different button, the values in the array seem to disappear. Any help will be appreciated. I placed comments in the code. I running php 5.2.5. Thanks.

<?php
/*****************8 Connect to database ******************/
mysql_connect("localhost", "root", "") or die(mysql_error());
mysql_select_db("pluto_media") or die(mysql_error());

/****************** Set Title ****************************/
Echo "<html>";
Echo "<title>HTML with PHP</title>";

/***************** Variables ****************************/
$i = 0;
$querStr = $_POST['querStr'];
$mediaSubTypeEnum = array (1 => "TV Shows",2 => "Movies",3 => "Home Videos", 4 => "Sports Events", 5 => "Music Videos", 6 => "Alternative", 7 => "Popular Music", 8 => "Classical Music");
$fileFormatEnum = array (1 => "Low Res",2 => "DVD",3 => "Standard Def", 4 => "HD 720", 5 => "HD 1080", 6 => "Low Quality", 7 => "MP3", 8 => "CD Quality", 9 => "High-def audio");


/******************* Create main body of html page **********************************************/
Echo  "
<body bgcolor='Green'>
<form action=".$_SERVER['PHP_SELF']." method='post'>
Search For:<input name='querStr' type='text' size='10'/>
<input type='submit' name='submit' value='submit'>";



/**************** perform action after button is clicked ***************************************/
if(isset($_POST['submit'])) {	//If the initial button displayed is clicked
	$result = mysql_query("SELECT * FROM File Where Filename LIKE '%".$querStr."%'");	
	Echo "	<input type='submit' name='submit2' value='submit2'> // output results of query in html table - this works fine
	<table border='1'>
	<tr>
		<th>Primary File</th>
		<th>Update File</th>
		<th>Filename</th>
		<th>Path</th>
		<th>MediaSubType</th>
		<th>FileFormat</th>
		<th>PK_File</th>
	</tr>";		    

	while($row = mysql_fetch_array($result)) {
		echo "<tr>";
			echo "<td><input type='radio' name='primary[]' value=$i/></td>";
			echo "<td><input type='checkbox' name='CopyFile[]' value='$i'/></td>";
			echo "<td>".$row['Filename']."</td>";
			echo "<td>".$row['Path']."</td>";			
			echo "<td>".$mediaSubTypeEnum[$row['FK_MediaSubType']]."</td>";
			echo "<td>".$fileFormatEnum[$row['FK_FileFormat']]."</td>";                               

			$myArray[$i++] = $row['PK_File'];
			echo "<td>".$myArray[$i-1]." -".$i."</td>";
		echo "</tr>";
	}
	echo "</table>";	
}


/**************** perform action after second button is clicked ***************************************/
if(isset($_POST['submit2'])) {
	foreach($_POST['primary'] as $value) { // determine which radio button is selected
		$value = $value + 1;
		echo "the primary is".$value."\n";
	}

for ($i = 0; $i < 10; $i++) { 
/* simple test to see if anything is in myArray. the array appears to be empty. This is the problem area. Before the second button was clicked
the array had verified values in it.*/
	echo $_REQUEST["myArray[$i]"];
	echo " in loop".$i;
}

$result = mysql_query("SELECT * FROM Picture_File Where FK_File = '".$myArray[$value]."'");		
$row = mysql_fetch_array($result);
$FK_Picture = $row['FK_Picture'];
$priVal = $value;	
echo "prival and fk_pic = ".$priVal. " - ".$FK_Picture."\n";
foreach($_POST['CopyFile'] as $value) {
	$value = $value + 1;
	mysql_query("INSERT INTO `Picture_File` VALUES ($FK_Picture,$myArray[$value],NULL,NULL,NULL,0,NULL,NULL)");
	mysql_query("UPDATE File SET mediaSubTypeEnum='.mediaSubTypeEnum[$priVal].' fileFormatEnum='.$fileFormatEnum[$priVal].' WHERE FK_File='.$myArray[$value].'");
}
}

Echo "	</form>
	   </body>
	</html>";
?>

[changed 'code' tags to 'php' tags -- MOD]

NogDog

Once a PHP script completes, all variables, constants, etc. are lost, as the entire script is cleared from memory. If you want values to persist across multiple calls to a script, you'll need to implement some sort of data persistence mechanism, such as PHP sessions (and the $_SESSION super-global array).

lon22

thanks for the reply NogDog. I tried to used an array as a session variable with no luck.
I added session_start(); to beginning of script. then:

$_SESSION["$myArray[$i++]"] = $someval;

I didn't save the variable. Can you post the correct way to save an array as a session variable.

Thanks

lon22

NogDog

Did you start the script with a session_start(); command?

lon22

Yes I used that command at the beginning of the script.

lon22

Thanks for the replies. I decided to go with a hidden field.

To save data:
$saveStr = implode(",",$myArray);
echo $saveStr;
echo "<input type='hidden' id='arry' name='myArray' value='".$saveStr."'/>";

To retrieve data:
$saveStr = $_POST['myArray'];
echo $saveStr;
$myArray = explode(",",$saveStr);

Worked like a charm.

Gigantor

nice trick..i never realised one could use a hidden field to hold an entire array, only invidual variables. thanks !

bradgrafelman

Note that using a hidden form field allows the data to be manipulated (as well as increasing the amount of data POST'ed, though that may be insignificant to you depending on how you look at it).

Gigantor

bradgrafelman ; how can the data be manipulated? assuming you echo the html and it is not viewable source, are you talking about attacks intercepting the POST data ?

bradgrafelman

Gigantor wrote:
assuming you echo the html and it is not viewable source

There's no such thing as "not viewable source" when you're talking about HTML - all HTML code (including hidden input fields) can be edited to your liking. For plenty of users who have the WebDeveloper addon for FireFox, this can be done in 2 mouse clicks.

In addition, I use sessions simply because I find this:

$_SESSION['var'] = $value;

easier than this:

echo '<input type="hidden" name="var" value="' . htmlentities($value) . '" />';