Simplify php validation of array from form-input - php

Question

I'm creating a page where you can save your predictions for soccermatches.
Every week there are 9 matches and a user can post his prediction for a match via a form.
The result of this form will result in the following array:
Array
(
[week] => 12
[game_id_1] => 28
[game_1_home] => 2
[game_1_away] => 2
[game_id_2] => 29
[game_2_home] => 2
[game_2_away] => 1
[game_id_3] => 31
[game_3_home] => 4
[game_3_away] => 0
[game_id_4] => 30
[game_4_home] => 2
[game_4_away] => 0
[game_id_5] => 32
[game_5_home] => 0
[game_5_away] => 2
[game_id_6] => 33
[game_6_home] => 1
[game_6_away] => 0
[game_id_7] => 35
[game_7_home] => 1
[game_7_away] => 1
[game_id_8] => 34
[game_8_home] => 2
[game_8_away] => 4
[game_id_9] => 36
[game_9_home] => 3
[game_9_away] => 0
)
I already wrote a validation part for the first match but instead of copying this 8 times I think this can go much easier.
Anyone an idea how to do this and please give me advice if I can improve this piece of code.
$blnOK = true;
$strResult = "";
if ($_SERVER["REQUEST_METHOD"] == "POST")
{
if (isset($_POST['game_id_1']) && !empty($_POST['game_1_home']) && !empty($_POST['game_1_away']))
//check if the posts are not empty, then put in variables
{
$strGame_id_1 = $_POST['game_id_1'];
$strGame_1_home = $_POST['game_1_home'];
$strGame_1_away = $_POST['game_1_away'];
//Check if strings are numeric
if ((ctype_digit($strGame_1_home)) && (ctype_digit($strGame_1_away)))
{
//Check if prediction already exists in database for user
$strQueryPrediction = "SELECT count(id) amount FROM prediction where player_id = 1 and game_id = $strGame_id_1";
$resultQueryPrediction = mysql_query ($strQueryPrediction);
$intPredictionKnown = mysql_result($resultQueryPrediction, 0);
if ($intPredictionKnown == 0)
{
//NOT KNOWN so INSERT
$blnOK = executeQuery("INSERT INTO prediction (player_id, game_id, predict_home, predict_away) VALUES (1, $strGame_id_1, $strGame_1_home, $strGame_1_away)", $strErrorText, $db);
echo "Your prediction is saved";
}
else
{
//KNOWN so UPDATE
$blnOK = executeQuery("UPDATE prediction SET predict_home = $strGame_1_home, predict_away = $strGame_1_away WHERE player_id = 1 AND game_id = $strGame_id_1", $strErrorText, $db);
echo "Your prediction is updated";
}
}
else
{
$strResult = "Too bad, your prediction could not saved.";
$blnOK = false;
}
}
else
{
echo "Input is empty";
}
}

Answer 1

You could, and arguably should, use a loop to save you copying the code a number of times. You say there are 9 games, so you can do the following :
$blnOK = true;
$strResult = "";
if ($_SERVER["REQUEST_METHOD"] == "POST")
{
for ($i = 1; $i <= 9; $i++)
{
if (isset($_POST['game_id_' . $i]) && !empty($_POST['game_' . $i . '_home']) && !empty($_POST['game_' . $i . '_away']))
//check if the posts are not empty, then put in variables
{
$strGame_id = $_POST['game_id_' . $i];
$strGame_home = $_POST['game_' . $i . '_home'];
$strGame_away = $_POST['game_' . $i . '_away'];
//Check if strings are numeric
if ((ctype_digit($strGame_' . $i . '_home)) && (ctype_digit($strGame_' . $i . '_away)))
{
//Check if prediction already exists in database for user
$strQueryPrediction = "SELECT count(id) amount FROM prediction where player_id = 1 and game_id = $strGame_id";
$resultQueryPrediction = mysql_query ($strQueryPrediction);
$intPredictionKnown = mysql_result($resultQueryPrediction, 0);
if ($intPredictionKnown == 0)
{
//NOT KNOWN so INSERT
$blnOK = executeQuery("INSERT INTO prediction (player_id, game_id, predict_home, predict_away) VALUES (1, $strGame_id, $strGame_home, $strGame_away)", $strErrorText, $db);
echo "Your prediction is saved";
}
else
{
//KNOWN so UPDATE
$blnOK = executeQuery("UPDATE prediction SET predict_home = $strGame_home, predict_away = $strGame_away WHERE player_id = 1 AND game_id = $strGame_id", $strErrorText, $db);
echo "Your prediction is updated";
}
}
else
{
$strResult = "Too bad, your prediction could not saved.";
$blnOK = false;
}
}
else
{
echo "Input is empty";
}
}
}
Whenever you have to do something multiple times, think of using a loop if possible, or creating a function which you can call multiple times.