PHP Complete Form

Php Complete form example will be shown in this chapter:

Let’s look at how to maintain input field data saved even after the form has been submitted.

PHP Complete Form-Keep field value

We add a small PHP script inside the value attribute of the following input fields: name, email, and website, to show the values in the input fields after the user presses the submit button.

Syntax


<input type="text" name="name" value="<?php echo $name;?>">

Radio Buttons: After that, we must show which radio button was selected. To do so, we’ll use the checked attribute (rather than the value attribute for radio buttons):

Syntax

<?php if (isset($gender) && $gender=="female") echo "checked";?>

This line will be added to save the data of radio button still after form submission.

PHP Complete Form Example

<!DOCTYPE HTML>  
<html>
<head>
<style>
.error {color: #FF0000;}
</style>
</head>
<body>  

<?php
// define variables and set to empty values
$nameError = $emailError = $genderError = $websiteError = "";
$name = $email = $gender = $comment = $website = "";

if ($_SERVER["REQUEST_METHOD"] == "POST") {
  if (empty($_POST["name"])) {
    $nameError = "Name is required";
  } else {
    $name = check_input($_POST["name"]);
    // check if name only contains letters and whitespace
    if (!preg_match("/^[a-zA-Z-' ]*$/",$name)) {
      $nameError = "Only letters and white space allowed";
    }
  }
  
  if (empty($_POST["email"])) {
    $emailError = "Email is required";
  } else {
    $email = check_input($_POST["email"]);
    // check if e-mail address is well-formed
    if (!filter_var($email, FILTER_VALIDATE_EMAIL)) {
      $emailError = "Invalid email format";
    }
  }
    
  if (empty($_POST["website"])) {
    $website = "";
  } else {
    $website = check_input($_POST["website"]);
    // check if URL address syntax is valid
    if (!preg_match("/\b(?:(?:https?|ftp):\/\/|www\.)[-a-z0-9+&@#\/%?=~_|!:,.;]*[-a-z0-9+&@#\/%=~_|]/i",$website)) {
      $websiteError = "Invalid URL";
    }    
  }

  if (empty($_POST["comment"])) {
    $comment = "";
  } else {
    $comment = check_input($_POST["comment"]);
  }

  if (empty($_POST["gender"])) {
    $genderError = "Gender is required";
  } else {
    $gender = check_input($_POST["gender"]);
  }
}

function check_input($data) {
  $data = trim($data);
  $data = stripslashes($data);
  $data = htmlspecialchars($data);
  return $data;
}
?>

<h2>PHP Form Validation Example</h2>
<p><span class="error">* required field</span></p>
<form method="post" action="<?php echo htmlspecialchars($_SERVER["PHP_SELF"]);?>">  
  Name: <input type="text" name="name" value="<?php echo $name;?>">
  <span class="error">* <?php echo $nameError;?></span>
  <br><br>
  E-mail: <input type="text" name="email" value="<?php echo $email;?>">
  <span class="error">* <?php echo $emailError;?></span>
  <br><br>
  Website: <input type="text" name="website" value="<?php echo $website;?>">
  <span class="error"><?php echo $websiteError;?></span>
  <br><br>
  Comment: <textarea name="comment" rows="5" cols="40"><?php echo $comment;?></textarea>
  <br><br>
  Gender:
  <input type="radio" name="gender" <?php if (isset($gender) && $gender=="female") echo "checked";?> value="female">Female
  <input type="radio" name="gender" <?php if (isset($gender) && $gender=="male") echo "checked";?> value="male">Male
  <input type="radio" name="gender" <?php if (isset($gender) && $gender=="other") echo "checked";?> value="other">Other  
  <span class="error">* <?php echo $genderError;?></span>
  <br><br>
  <input type="submit" name="submit" value="Submit">  
</form>

<?php
echo "<h2>Your Input:</h2>";
echo $name;
echo "<br>";
echo $email;
echo "<br>";
echo $website;
echo "<br>";
echo $comment;
echo "<br>";
echo $gender;
?>

</body>
</html>