how to access another php file from a form ? - php

Question

I'm doing the form validation using php.I'm trying to access the php file from my form(<form action="appoint.php">).But it shows me undefined variable error at each of the form elements.(code works well when i use the
<form method="post" action="<?php echo htmlspecialchars($_SERVER["PHP_SELF"]);?>">which means i used form(html) and php in the same file.
here is my form code:
<form method="post" action="appoint.php">First Name:
<input type="text" name="fname" value="<?php echo $fname;?>"> <span class="error">* <?php if(isset($error['fname']))
echo $error['fname'];?></span>
<br>
<br>Last Name:
<input type="text" name="lname" value="<?php echo $lname;?>"> <span class="error">* <?php if(isset($error['lname']))
echo $error['lname'];?></span>
<br>
<br>E-mail:
<input type="text" name="email" value="<?php echo $email;?>"> <span class="error">* <?php if(isset($error['email']))
echo $error['email'];?></span>
<br>
<br>Phone-no:
<input type="text" name="phone_no" value="<?php echo $phone_no;?>"> <span class="error">* <?php if(isset($error['phone_no']))
echo $error['phone_no'];?></span>
<br>
<br>Date:
<input type="text" name="date" value="<?php echo $date;?>"> <span class="error">* <?php if(isset($error['date']))
echo $error['date'];?></span>
<br>
<br>Time:
<input type="text" name="time" value="<?php echo $time;?>"> <span class="error">* <?php if(isset($error['time']))
echo $error['time'];?></span>
<br>
<br>Physician:
<input type="text" name="physician" value="<?php echo $physician;?>"> <span class="error">* <?php if(isset($error['physician']))
echo $error['physician'];?></span>
<br>
<br>Remarks :
<input type="text" name="remarks" value="<?php echo $remarks;?>"> <span class="error">* <?php if(isset($error['remarks']))
echo $error['remarks'];?></span>
complaint:
<textarea name="complaint" rows="5" cols="40" value="<?php echo $complaint;?>"></textarea> <span class="error">* <?php if(isset($error['complaint']))
echo $error['complaint'];?></span>
<br>
<br>
<input type="submit" name="submit" value="Submit">
</form>
and here is my appoint.php
`
$data = htmlspecialchars($data);
return $data;
}
if ($_SERVER["REQUEST_METHOD"] == "POST")
{
if (empty($_POST["fname"]))
{$error['fname']= "First Name is required";}
else
{
$fname = test_input($_POST["fname"]);
// check if name only contains letters and whitespace
if (!preg_match("/^[a-zA-Z ]*$/",$fname))
{
$error['fname'] = "Only letters and white space allowed";
}
}
if (empty($_POST["lname"]))
{$error['lname']= "Last Name is required";}
else
{
$lname = test_input($_POST["lname"]);
// check if name only contains letters and whitespace
if (!preg_match("/^[a-zA-Z ]*$/",$lname))
{
$error['lname'] = "Only letters and white space allowed";
}
}
if (empty($_POST["email"]))
{$error['email'] = "Email is required";}
else
{
$email = test_input($_POST["email"]);
// check if e-mail address syntax is valid
if (!preg_match("/([\w\-]+\#[\w\-]+\.[\w\-]+)/",$email))
{
$error['email'] = "Invalid email format";
}
}
if (empty($_POST["phone_no"]))
{$phone_no = '00-0000-0000';}
else
{
$phone_no = test_input($_POST["phone_no"]);
// check if phone.no is valid//
if(!preg_match("/^[0-9]{2}-[0-9]{4}-[0-9]{4}$/", $phone_no))
{
$error['phone_no'] = "Invalid Number";
}
}
if (empty($_POST["date"]))
{$error['date'] = "Date is required";}
else
{$date= test_input($_POST["date"]);}
if (empty($_POST["time"]))
{$error['time'] = "Time is required";}
else
{$time = test_input($_POST["time"]);}
if(empty($_POST["physician"]))
{$error['physician']="select a physician";}
else {$physician=test_input($_POST["physician"]);
}
if (empty($_POST["remarks"]))
{$error['remarks'] ="";}
else
{
$remarks = test_input($_POST["remarks"]);}
if (empty($_POST["complaint"]))
{$error['complaint'] = " complaint is required";}
else
{
$complaint = test_input($_POST["complaint"]);}
if(empty($error))
{$con=mysqli_connect("localhost","root","root","my_db1");
// Check connection
if (mysqli_connect_errno())
{
echo "Failed to connect to MySQL: " . mysqli_connect_error();
}
$sql="INSERT INTO np_appointment(fname,lname,date,time,email,phone_no,
physician,remarks,complaint)
VALUES
('$_POST[fname]','$_POST[lname]','$_POST[date]',
'$_POST[time]','$_POST[email]','$_POST[phone_no]',
'$_POST[physician]','$_POST[remarks]','$_POST[complaint]')";
if (!mysqli_query($con,$sql))
{
die('Error: ' . mysqli_error($con));
}
echo "1 record added";
mysqli_close($con); }
}
?>
`

Answer 1

You can try a different approach:
Make all the fields required in html.
<input type="text" name="fname" value="<?php echo $fname;?>" required>
Then on the php do this. Define the variable outside the if-else sections.:
$fname = '';
if (empty($_POST["fname"]))
{$error['fname']= "First Name is required";}
else
{
$fname = test_input($_POST["fname"]);
}