function bookingForm() {
  var error = 0;
  // Check the name is entered
  if(document.getElementById('fullname') != null) {
    var item = document.getElementById('fullname');
    if(item.value == '') {
      alert('Please enter a name');
      item.setAttribute("class", 'input_medium, input_error_medium');
      item.focus();
      error = 1;
    } else {
      item.setAttribute("class", "input_medium");
    }
  }
  
  // Check the first line of address is entered
  if(document.getElementById('address1') != null) {
    var item = document.getElementById('address1');
    if(item.value == '') {
      alert('Please enter the first line of your address');
      item.setAttribute("class", 'input_medium, input_error_medium');
      if(error == 0) {
        item.focus();
      }
      error = 1;
    } else {
      item.setAttribute("class", "input_medium");
    }
  }
  
  // Check the postcode is entered
  if(document.getElementById('postcode') != null) {
    var item = document.getElementById('postcode');
    if(item.value == '') {
      alert('Please enter the postcode');
      item.setAttribute("class", 'input, input_error');
      if(error == 0) {
        item.focus();
      }
      error = 1;
    } else {
      item.setAttribute("class", "input");
    }
  }
  
  // Check the contact number is entered
  if(document.getElementById('contactNumber') != null) {
    var item = document.getElementById('contactNumber');
    if(item.value == '') {
      alert('Please enter a contact number');
      item.setAttribute("class", 'input, input_error');
      if(error == 0) {
        item.focus();
      }
      error = 1;
    } else {
      item.setAttribute("class", "input");
    }
  }  
    
  // Check the date
  if(document.getElementById('date') != null) {
    var item = document.getElementById('date');
    if(item.value == 'DD/MM/YYYY') {
      alert('Please enter a date of arrival');
      item.setAttribute("class", 'input, input_error');
      if(error == 0) {
        item.focus();
      }
      error = 1;
    } else {
      item.setAttribute("class", "input");
    }
  }
        
    
  if(error == 0) {
    return true;
  } else if(error == 1) {
    return false;
  }

} // function