How to make value in form POST to same page? - php

Question

I have to make everything happened on the same page. I have used action="<?PHP echo $_SERVER['PHP_SELF']; ?>" here but it is not working. I have insert the PHP query below the form. Basically, my question is how do I make sure the form is posting the values on the same page. If it is updated, a pop up will come up.
$user_id=$_SESSION['user_id'];
$date = date("l jS \of F Y h:i:s A");
$query1 ="SELECT daily_limit FROM user WHERE user_id='$user_id'";
$result1 = mysqli_query($link, $query1) or die(mysqli_error($link));
while ($row1 = mysqli_fetch_array($result1)) {
$dailylimit=$row1['daily_limit'];
}
$query2 = "SELECT SUM(debit) AS debited_today FROM transaction WHERE user_id = '$user_id' AND date = CURRENT_DATE" ;
$result2 = mysqli_query($link, $query2) or die (msqli_error($link));
while ($row2 = mysqli_fetch_array($result2)){
$debited_today = $row2['debited_today'];
}
// form
<form method="POST" action="<?PHP echo $_SERVER['PHP_SELF']; ?>" >
<table id="table">
<tr>
<td class="alt">Existing Daily Limit</td>
<td>S$ <?php echo $dailylimit; ?> </td>
<input type="hidden" name="dailylimit" value="<?php echo $dailylimit ?> "/>
</tr>
<tr>
<td class="alt"><label for="newdailylimit">New Daily Limit</label></td>
<td>$ <select name="newdailylimit">
<option value="100.00">100.00</option>
<option value="500.00">500.00</option>
<option value="1000.00">1000.00</option>
<option value=5000.00">5000.00</option>
</select></td>
</tr>
<tr>
<td class="alt">Amount Debited Today</td>
<td>S$ <?php echo $debited_today; ?></td>
</tr>
<tr>
<td class="alt">Amount Debited Left</td>
<td>S$ <?php echo ($dailylimit - $debited_today); ?> </td>
</tr>
</table>
<br/>
<input type="submit" name="submit "value="Submit"></input>
</form>
// Values I need to POST
$dailylimit = $_POST['dailylimit'];
$newdailylimit = $_POST['newdailylimit'];
if ($dailylimit != $newdailylimit){
$query = "UPDATE user SET daily_limit='$newdailylimit' WHERE user_id='$user_id'";
$result = mysqli_query($link, $query) or die(mysqli_error($link));
echo "<script>alert('You have successfully updated your daily limit');</script>";
}
else if ($dailylimit == $newdailylimit){
echo "<script>alert('You have selected the same daily limit as your previous one. Please choose a different one. ');</script>";
}
else{
}

Answer 1

Ahh I may have found out what the problem is:
You have a space after the word submit and no space before value.
This will prevent your form from submitting.
<input type="submit" name="submit "value="Submit"></input>
---^ ^
Change this to:
<input type="submit" name="submit" value="Submit">
The double quote might mess things up.
Other things that are wrong but won't fix your problem
Also
<option value=5000.00">5000.00</option>
should be
<option value="5000.00">5000.00</option>
Also
<input type="hidden" name="dailylimit" value="<?php echo $dailylimit ?> "/>
// You have an extra space here ^
Which will change your $dailylimit, and append it with a space.

Answer 2

make your action=''. it will post to itself.
then on top of your page check if the request is post ex. if($_POST){//add your code}else{//yourform}