PHP - Make Varialble Null

hi all,

i have a script in where the user enters there post code and it will provide a price for delivery, how would i echo "please contact us for price" if the db record for the price is (null) or empty??


 <?php
mysql_connect ("localhost", "root","password")  or die (mysql_error());
mysql_select_db ("postcode");
$term = $_POST['term'];
$sql = mysql_query("SELECT * FROM uk_postcodes, zones WHERE postcode LIKE '%$term%' AND zone_id = zone_large ");
while ($row = mysql_fetch_array($sql)){
    echo '<br/> Postcode: '.$row['postcode'];
    echo '<br/> Town: '.$row['town'];
    echo '<br/> County: '.$row['county'];
    echo '<br/> Small: &pound;'.$row['price_s'];
    echo '<br/> Medium: &pound;'.$row['price_m'];
    echo '<br/> Large: &pound;'.$row['price_l'];
    echo '<br/><br/>';
    }
    
?>

2 PART QUESTION (so I don't have to ask two questions 😀  )

1.)
My script has tons of PHP variables. Is it better to declare them all at the top of my page like this:
$cat = $words = $day = $lunch = $user = $address = $potato = $_SESSION["goodpeople"] = $dumbquestionList = $b = $hundredMoreVariables = "";
-or-
as needed, like this:
$cat = "";  if($day == 'Thursday') { $cat = 'time_to_feed'; }
$words = "";  $school = array('teachers'=>'boring','lunch'=>'free'); $words = $school['teachers'];
$_SESSION["goodpeople"] = ""; if($_SESSION["goodpeople"] == "" { $_SESSION["goodpeople"] = 'Gandhi'; }

2.)
What are the pros and cons of declaring variables as NULL and using " isset " versus declaring variables as "" and using ==
Example:
$cat = $words = $day = $lunch = $user = $address = NULL;
if( !isset($cat)) { $cat = 'black'; }.........................if(isset($day)) { $sleep = 'none'; }..............etc., etc.
-or-
$cat = $words = $day = $lunch = $user = $address = "";
if($cat == "") { $cat = 'black'; }............................ if($day != "") { $sleep = 'none'; }................etc., etc.

On my particular coding, I can use either the NULL/isset style, or, the ""/== style, with no errors or ill effects.... but something tells me the expert PHP coders prefer one over the other...

Thank you!!

Edited July 10 by ChenXiu

How can I change Yes to No for the NULL field in the mysql db structure.


E.g. (Table name: address and Column name : state)
<?php
$link = mysql_connect("localhost","db","pw");
mysql_select_db("db");

mysql_query("alter table address modify state null NO); 
$result = mysql_query($query);
$sent = "Edit Successful.";
echo ($sent);
?>

I'm trying to display the null values only, where am I going wrong?

SELECT IFNULL(trans, 0) AS 'Transactions', customer.cID AS 'Customer ID', customer.surname AS 'Surname'
FROM customer
LEFT JOIN account
ON (account.cID = customer.cID)
WHERE IFNULL(trans, 0);

I'm trying to force a NULL value into the database with a hidden value and I can't seem to get it to work.

Any suggestions?

<input type="hidden" name="inactive" value=""/>


I also tried here too:

$sql="UPDATE product SET inactive='NULL' WHERE id = '$item_id'";

I have an array which can be empty; in this case, I get error. I want to skip when the array is empty.

When calling the array from file, I use the following code if (file_exists($array_file)) { 
"the doing code"
} else {
echo "File does not exist";
}


How I should use this If Else condition when array comes from a string like  $test_array = explode(', ', $examplestring, -1);

I have a for loop that I am looping through. When I use var_dump() I get 10 results (which is what I should be getting). However, when I loop through it using a for() loop I am getting an extra 11th value that is blank. What would be causing this? My code is below:

Code: [Select]
$legacy = new Legacy();
// Loop through each film in the shopping cart
for ($i = 0; $i < $myShoppingCartInfo['row_count']; $i++) {
// Determine if the film is of a legacy series
if ($legacy->isLegacyCheckout($myShoppingCartInfo['data']['PRODUCTSKUID'][$i])) {
// Declare array to hold all legacy film entity_id values
$legacyEntityIds = array();
$legacyEntityIds = $legacy->getLegacyEntityIds($myShoppingCartInfo['data']['PRODUCTSKUID'][$i]);
var_dump($legacyEntityIds);
// Loop through all legacy video entity_id's
for ($i = 0; $i < $legacyEntityIds['data']['ENTITY_ID']; $i++) {
// Grant streaming access to each entity id
echo $legacyEntityIds['data']['ENTITY_ID'][$i] . '<br />';
// Insert the product into the order items table
/*$query = "INSERT INTO tblOrderItems (OrderItemID, ProductSKUID, RentalDate, OrderID)
VALUES (##newID##,
'".$myShoppingCartInfo['data']['PRODUCTSKUID'][$i]."',
".($myShoppingCartInfo['data']['RENTALDATE'][$i] === NULL ? 'NULL' :
"'".$myShoppingCartInfo['data']['RENTALDATE'][$i]."'").", ".$newOrderID.")";
$cartItemInserted = counter_id_insert($query,'OrderItemID');
$curr_user->addNewEntityLicense($legacyEntityIds['data']['ENTITY_ID'][$i]);*/
}
}

When I view the source code of the output page in a browser, this is what I see:
array(5) {
  ["row_count"]=>
  int(10)
  ["col_count"]=>
  int(1)
  ["col_names"]=>
  array(1) {
    =>
    string(9) "entity_id"
  }
  ["col_types"]=>
  array(1) {
    =>
    string(3) "int"
  }
  ["data"]=>
  array(1) {
    ["ENTITY_ID"]=>
    array(10) {
      =>
      string(7) "1681799"
      [1]=>
      string(7) "1681872"
      [2]=>
      string(7) "1681871"
      [3]=>
      string(7) "1681870"
      [4]=>
      string(7) "1681869"
      [5]=>
      string(7) "1681868"
      [6]=>
      string(7) "1681867"
      [7]=>
      string(7) "1681866"
      [8]=>
      string(7) "1681865"
      [9]=>
      string(7) "1681864"
    }
  }
}
1681799<br />1681872<br />1681871<br />1681870<br />1681869<br />1681868<br />1681867<br />1681866<br />1681865<br />1681864<br /><br />

I have a php page where user/db info is being passed:


<?php
include "include/dbc.php";

include "include/header.inc";

$exerciseid = $_POST["exerciseid"];
$duration = $_POST["duration"];
$distance = $_POST["distance"];
$metric = $_POST["metric"];

echo'<h1>Added Activities</h1>';



// name of array
echo '<h1>Exercise</h1>';
if (is_array($exerciseid)) {
        foreach ($exerciseid as $key => $value) {

        echo $key .' : '. $value .'<br />';

        }
}



// name of array
echo '<h1>Duration</h1>';
if (is_array($duration)) {
        foreach ($duration as $key => $value) {

                        echo $key .' : '. $value .'<br />';

        }
}


// name of array
echo '<h1>Distance</h1>';
if (is_array($distance)) {
        foreach ($distance as $key => $value) {

                        echo $key .' : '. $value .'<br />';

        }
}

// name of array
echo '<h1>Metric</h1>';
if (is_array($metric)) {
        foreach ($metric as $key => $value) {

                        echo $key .' : '. $value .'<br />';

        }
}

?>


And here is the output from that code:

Added Activities

Exercise
0 : Canoeing, on camping trip
1 : Canoeing, rowing, over 6 mph, vigorous effort
2 : Canoeing, rowing, crewing, competition
3 : Canoeing, rowing, light effort
4 : Canoeing, rowing, moderate effort
5 : Diving, springboard or platform
6 : Kayaking
7 : Sailing, boat/board, windsurfing, general
8 : Sailing, in competition
9 : Skiing, water
10 : Ski-mobiling, water
11 : Skin diving, scuba diving, general
12 : Snorkeling
13 : Surfing, body or board
14 : Swimming laps, freestyle, fast, vigorous effort
15 : Swimming laps, freestyle, light/moderate effort
16 : Swimming, backstroke, general
17 : Swimming, breaststroke, general
18 : Swimming, butterfly, general
19 : Swimming, leisurely, general
20 : Swimming, sidestroke, general
21 : Swimming, sychronized
22 : Swimming, treading water, fast/vigorous
23 : Swimming, treading water, moderate effort
24 : Water polo
25 : Water volleyball
26 : Whitewater rafting, kayaking, or canoeing

Duration
Canoeing, on camping trip : 20
Canoeing, rowing, over 6 mph, vigorous effort :
Canoeing, rowing, crewing, competition :
Canoeing, rowing, light effort :
Canoeing, rowing, moderate effort :
Diving, springboard or platform :
Kayaking :
Sailing, boat/board, windsurfing, general :
Sailing, in competition :
Skiing, water :
Ski-mobiling, water :
Skin diving, scuba diving, general :
Snorkeling :
Surfing, body or board :
Swimming laps, freestyle, fast, vigorous effort :
Swimming laps, freestyle, light/moderate effort :
Swimming, backstroke, general :
Swimming, breaststroke, general :
Swimming, butterfly, general :
Swimming, leisurely, general :
Swimming, sidestroke, general :
Swimming, sychronized :
Swimming, treading water, fast/vigorous :
Swimming, treading water, moderate effort :
Water polo :
Water volleyball :
Whitewater rafting, kayaking, or canoeing :

Distance
Canoeing, on camping trip : 20
Canoeing, rowing, over 6 mph, vigorous effort :
Canoeing, rowing, crewing, competition :
Canoeing, rowing, light effort :
Canoeing, rowing, moderate effort :
Diving, springboard or platform :
Kayaking :
Sailing, boat/board, windsurfing, general :
Sailing, in competition :
Skiing, water :
Ski-mobiling, water :
Skin diving, scuba diving, general :
Snorkeling :
Surfing, body or board :
Swimming laps, freestyle, fast, vigorous effort :
Swimming laps, freestyle, light/moderate effort :
Swimming, backstroke, general :
Swimming, breaststroke, general :
Swimming, butterfly, general :
Swimming, leisurely, general :
Swimming, sidestroke, general :
Swimming, sychronized :
Swimming, treading water, fast/vigorous :
Swimming, treading water, moderate effort :
Water polo :
Water volleyball :
Whitewater rafting, kayaking, or canoeing :

Metric
0 : mile
1 : mile
2 : mile
3 : mile
4 : mile
5 : mile
6 : mile
7 : mile
8 : mile
9 : mile
10 : mile
11 : mile
12 : mile
13 : mile
14 : mile
15 : mile
16 : mile
17 : mile
18 : mile
19 : mile
20 : mile
21 : mile
22 : mile
23 : mile
24 : mile
25 : mile
26 : mile


As you can see, null values are being passed as well. I am hoping that someone can show me the correct way to use php unset to get rid of these null values. Thank you.

Can someone help me to get this code working...

Code: [Select]
public function getBowlContents(){
if is_null($this->contents) {
return "The bowl is empty!";
} else {
return "The bowl contains " . $this->contents . " soup!";
}


TomTees

Hi...
i have table
EMP_NO
LOGIN - DATETIME, NULL
LOGOUT - DATETIME, NULL

I have this query:

Code: [Select]
<?php

include 'config.php';

$currentEmpID = $_SESSION['empID']; 
 
 if(!isset($_POST['submit_'])){ 
     
    $DATE1 = $_POST['firstinput'];
    $DATE2   = $_POST['secondinput'];
    
  
 $sql = "SELECT EMP_NO, LOGIN, LOGOUT  FROM employee_attendance WHERE DATE(LOGIN) BETWEEN '$DATE1' AND '$DATE2'";
    $attendance = $conn3->GetAll($sql);
   
    $smarty->assign('attendance', $attendance);

 }
 $smarty->display('header_att.tpl');
 $smarty->display('empAttendance.tpl');
 $smarty->display('footer.tpl');
  
?>

My problem is I have data
EMP_NO 00000223
LOGIN NULL
LGOUT NULL

this data was not displayed because it has a null value.. i want it to displayed also and highlight it because it has a value null..

Thank you

I have two drop down boxes that give me the result $extract and $extract2. The user can not pick the same seat in each drop down box.
I am having a problem getting my IF statement to work, well it is working but not as I would like. When the page loads both boxes are null and are therefore the the same and the 'else' statement is shown.

Is there a way to say...IF button is NULL on the page load then ignore?



//SUBMIT BUTTON
echo "<br>";
echo "<br>";
echo "<input type='submit' name='select' value='Select Seats'>";
echo "</form>";

//IF TO SEE IF TWO SEATS ARE SAME
if ($_POST['select']="")
{
echo "please choose seats";
}
if ($_SESSION['extract']==$_SESSION['extract2'])
{
echo "You have choosen the same seat twice, please choose two different seats.
<a href='confirm.php'> Go Back</a>";
}




Thanks. =)

Greetings folks,

I've tried searching on this but couldn't find anything which I think is odd since I'm sure I'm not the first person with this question...


I have a project that is basically a big (really big) form.  When the user hits submit they get a CSV file. My client will then import the CSV into their database.  The CSV is made up of two lines, the first being field names and the second line being the field values.  Both the names and values are pulled from $_POST.

The CSV looks like this:

"Name","Age","Favorite Color"
"Bob","12","Purple"

The problem I having is if the user skips a question, let's say Age for this example, the CSV will look like this:

"Name","Age","Favorite Color"
"Bob","Purple"

The clients database then freaks when it sees the value for Age is Purple.  So my question is, how does one handle null values from from $_POST to avoid such an issue?

Thank you!  Thank you!  Thank you! 

Okay, so, I have a script that allows a forum inside of a room in a game.

If you want a forum, you mark Yes from a dropdown menu inside the editing portion of the room. It will then save that room's title into a field called `board` in the database.

However, when you mark No from the dropdown, it still leaves it in there. I don't want this. I want it to change to NULL.

How do I go about doing this?

Here's my current coding:


if (!islevel($p,$co)) newlevel($p,$co);
setlevel($p,$co,"title",filter(stripslashes($title)));
setlevel($p,$co,"board",filter(stripslashes($title)));
}


Explanations:
setlevel just connects to the database and inserts these values.
$title is obviously the title of the room
$co = coordinates for the room

Here is the editing page, where the dropdown menu is:


<table width=100% style=text-align:center><tr>
<td>BOARD:<br />
<select name=b>
  <option value=0>No</option>
  <option value=1 <? if ($b == 1) echo "selected"
  ?>>Yes</option></select><br />Was <?=$b?>
</tr></table>

Good morning,   I am trying to convert a mssql query into json format so that I can then later pass this through google's visualisation api. The query and encoding seems to be working but the encode returns NULL.   I have checked the normal gotcha's of making sure its utf8 encoded and that I have used a version of PHP that has the encode (using php 5.3.19).   Can any one help me with getting the encode to work.   PHP CODE:     <?php

will this code check if value is null 

Code: [Select]
if($_SESSION["cart"] != null)