my code : querybuilder.php

public function addtasktodb($title,$description,$who,$completed)
	{
		$statement = $this->pdo->prepare("INSERT INTO todos(`title`, `description`, `who`, `completed`) VALUES('$title','$description','$who',$completed)");
		if ($statement->execute()) {
            //$_SESSION['status']="Succesfully added";
            header("Location: http://localhost:8888");
        } else {
            echo 'An error occured.';
        }
	}

controller////addTasktoDb.php

<?php 

$addtasktodbtitle= $_POST['title'];
$addtasktodbwho= $_POST['who'];
$addtasktodbdescription= $_POST['description'];
$addtasktodbcompleted= $_POST['completed'];
$query->addtasktodb($addtasktodbtitle,$addtasktodbdescription,$addtasktodbwho,$addtasktodbcompleted);

 ?>

form:

<form method="POST" action="addtasktodb" style="margin: auto; width: 400px; text-align: center;" class="row g-3 needs-validation" novalidate>
  		<div>
		   	 <label for="title" class="form-label"><h3>TITLE</h3></label>
		    <input type="text" class="form-control" name="title" required>
    		<div class="valid-feedback">
     			 Looks good!
    		</div>
  		</div>
  		<div>
		    <label for="description" class="form-label">Description</label>
		    <input type="text" class="form-control" name="description" required>
		    <div class="valid-feedback">
      			Looks good!
    		</div>
  		</div>
  		<div>
		    <label for="who" class="form-label">Who</label>
		    <input type="text" class="form-control" name="who" required>
		    <div class="valid-feedback">
      			Looks good!
    		</div>
  		</div>
  		<div>
    		<fieldset>
    		<legend>Mark as Completed</legend>
    		<div>
    		<input type="radio" class="form-check-input" id="validationFormCheck1" name="completed" value="true"required>
    		<label class="form-check-label" for="validationFormCheck1">Yes</label>
  			</div>
  			<div>
    		<input type="radio" class="form-check-input" id="validationFormCheck2" name="completed" value="false" checked required>
    		<label class="form-check-label" for="validationFormCheck2">No</label>
  			</div>
  		</fieldset>
  		</div>
  		<div class="col">
    			<button class="btn btn-primary" type="submit">Submit</button>
  		</div>
</form>

i use bootsrtap.

and then the routes.php

$router->post('addtasktodb', 'controllers/addtasktodb.php');

Forms, Request Types, and Routing

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