display include only if value is posted

[webguync]

Hi, I only want to display some included PHP code only if a value is displayed from  form input. The value is a zip code which is used to display weather information, but the app produces an error when you first enter the page, because their is no value for the zip variable. I know I need an if/else statement, but not sure what to put in it.

 

The form code is this

<h3>Enter your zip code to receive weather info.</h3>
            	<form method="post" action="<?php echo $PHP_SELF;?>">
Enter Zip Code:<input type="text" size="12" maxlength="12" name="zip"><br /> 
<input id="submit" type="submit" name="Submit" value="Enter Zip"/>

</form>

<?php


// this is how we bring in the weather file

include 'weather_report.php' 

?>

 

the zip variable is set-up in the weather_report.php file as follows

$zip = $_POST["zip"];

 

but like I said until that value is set, an error is thrown by the weather app code.

 

 

[BlueSkyIS]

something like if the value is set, include? you are practically writing the code with your question. why not give it a try?

[litebearer]

in a very simplistic psuedo code way (no error checking, cleansing, etc)

<?php
$zip = $_POST['zip'];
/* check to see if its set, if its numeric, if it has proper length  etc etc */
/* if the above check produce and error message ie $error_mess = some content */
/* then send back to form */
if(errors) {
  back to form
}else{
include ('weather_report.php');
}
?>

[webguync]

thanks, is this the way to do the variable check? I ask b/c it doesn't seem to be working. I don't get the included code.

<form method="post" action="<?php echo $PHP_SELF;?>">
Enter Zip Code:<input type="text" size="12" maxlength="12" name="zip"><br /> 
<input id="submit" type="submit" name="Submit" value="Enter Zip"/>

</form>
<?php
$zip = $_POST['zip'];

/* check to see if its set, if its numeric, if it has proper length  etc etc */
/* if the above check produce and error message ie $error_mess = some content */
/* then send back to form */
if (!isset($zip)) {
    echo "please fill in a zip code value";
}
else{
include ('weather_report.php');
}
?>

 

[webguync]

does anyone see anything wrong with the code I posted?

[BlueSkyIS]

unless you've set it somewhere this value is empty: $PHP_SELF;

[BlueSkyIS]

other than that undefined value and a notice about $_POST['zip'] being an undefined index, it works for me. i submit a zip code and the include is included. You might want to turn your errors up all the way to get warnings and notices.

[fortnox007]

don't forget to filter $PHP_SELF

 

http://www.phpro.org/tutorials/PHP-Security.html

[BlueSkyIS]

also don't forget it's $_SERVER['PHP_SELF']. you can leave it out entirely, using action='' (empty).

[webguync]

so after reading these responses I believe this is what the form and if/else code should look like?

 

            	<form method="post" <?php echo filter_var($_SERVER['PHP_SELF'], FILTER_SANITIZE_STRING);?>
Enter Zip Code:<input type="text" size="12" maxlength="12" name="zip"><br /> 
<input id="submit" type="submit" name="Submit" value="Enter Zip"/>

</form>
<?php
$zip = $_POST['zip'];
echo $zip;
/* check to see if its set, if its numeric, if it has proper length  etc etc */
/* if the above check produce and error message ie $error_mess = some content */
/* then send back to form */
if (!isset($_POST['zip'])) {
    echo "please fill in a zip code value";
}
else{
include ('weather.php');
}
?>

 

 

[BlueSkyIS]

<form method="post" action=''>
Enter Zip Code:<input type="text" size="12" maxlength="12" name="zip"><br /> 
<input id="submit" type="submit" name="Submit" value="Enter Zip"/>
</form>
<?php
if (!isset($_POST['zip'])) {
    echo "please fill in a zip code value";
}
else{
include ('weather.php');
}
?>

[BlueSkyIS]

but you'll probably want to make sure the form was POST'ed before checking to see if $_POST['zip'] isset. otherwise, you'll get the error before you submit the form.

[webguync]

not sure I follow, how would I check that?

[BlueSkyIS]

<?php
if ($_SERVER['REQUEST_METHOD'] == "POST") {
    if (!isset($_POST['zip'])) {
        echo "please fill in a zip code value";
    } else {
        include ('weather.php');
    }
}
?>

[webguync]

seems to be working, thanks!