Displaying an error message.

[Ali_baba]

Good day,

I am trying to write a script that will get a value from previous script and display the results. If the script gets a value from previous script (user selects the value from radio button in previous script) then things go fine.

But when the script gets no value from previous script (means user don't select any radio button), I see an error that says "Warning: mysql_fetch_array(): supplied argument is not a valid MySQL result resource in /epshp/epshp_update.php on line 27"

Of course, I need to do a little changes but I don't know where and how. Can somebody help me or give me a clue? Thanks in advance.

The source code is here:

$record_ids=$_POST['modify'];
require ('access.php');
$result = mysql_query("SELECT record_id,note FROM ktl_epshp where ktl_epshp.record_id = $record_ids");

while ($array = mysql_fetch_array($result))  {
echo <<<EOD
<table align= "center">
<tbody>
  <tr>
  <td><form action="epshp_updatec.php" method ="post" />
  <input type="hidden" name="verify_epshp_updatec" value ="ok" />
  <table align = "center">
  <tbody>
    <tr>
    <td>Sairaanhoitopiiri:</td>
    <td>
.........

[mrhappiness]

$record_ids= empty($_POST['modify']) ? 0 : (int)$_POST['modify'];

if $POST['modify'] is empty you assign 0 zo $record_ids otherwise you assign the int-value of $POST['modify']

[Ali_baba]

Hello mrhappiness,

Thanks for reply. That was really helpful.

If I want to display an error messages like "You didn't select anything, hit back on browser", do I need to put if-else check outside of while loop or inside of it?

[mrhappiness]

If the user didn't select anything, empty($POST['modify']) evaluates to true and isset($POST['modify']) evaluates to false

check this outside the while... or preselect an entry 😉