我似乎无法纠正控制台正在谈论的错误任何人都可以帮助我。我的代码如下。我创建了一个网络表单，将数据保存到本地存储并将其显示在屏幕上，然后根据需要删除所有存储的数据。但出于某种原因，它根本不会从表单中获取数据。

// Wait until the DOM is ready 
window.addEventListener("DOMContentLoaded", function (){
  // getElementById function
  function $(x) {
    var theElement = document.getElementById(x);
    return theElement;
  } // end theElement function

  function makeCats () {
    var formTag = document.getElementsByTagName("form"), // form tag is an array
    selectListItem = $('select'),
    makeSelect = document.createElement('select'),
    makeSelect.setAttribute("id", "groups");
    for(var i=0, j=notesCategories; i<j; i++) {
      var makeOption = document.createElement('option');
      var optionText = notesCategories[i]
      makeOption.setAttribute("value", "optionText");
      makeOption.innerHTML = optionText;
      makeSelect.appendChild(makeOption);
    } // end for loop
    selectListItem.appendChild(makeSelect);
  } // end makeCat function

  function getSelectedRadioBtn() {
    var radio = document.forms[0].favNote 
    for (var i=0; i<radio.length; i++) {
      if(radio[i].checked) {
        favoriteValue = radio[i].value;
      } // end if
    } // end for loop
  } // end get selected radio btn function

  function getcheckedBoxBtn() {
    if($('fav').checked) {
      favoriteValue = $('fav').value;
    } else {
      favoriteValue = "No"
    }
  } // end function

  function toggleControls(a) {
    switch(a){
      case "on":
        $('noteForm').style.display = "none"
        $('clear').style.display = "inline"
        $('displayLink').style.display = "none"
        break
      case "off":
        $('noteForm').style.display = "block"
        $('clear').style.display = "inline"
        $('displayLink').style.display = "inline"
        $('items').style.display = "none"
        break
      default:
        return false;
    }
  }

  function saveNotes() {
    var id                  = Math.floor(Math.random()*1000001);
    // gather up all form fields values and store them in an object 
    // object properites will contain an array with form labels and input values 

    getSelectedRadioBtn(); // calls function
    getcheckedBoxBtn();
    var item                = {}
    item.group          = ["Group", $('groups').value ];
    item.notetitle      = ["Title", $('notetitle').value ];
    item.noteinfo       = ["Note", $('noteinfo').value ];
    item.date           = ["Date", $('date').value ];
    item.items          = ["Number of Itmes", $('items').value ];
    item.attach         = ["Attach a File", $('attach').value ];
    item.favorite       = ["Favorite Note", favoriteValue ];

    // save data into local storage. Use stringify to convert our object to a string 
    localStorage.setItem(id, JSON.stringify(item));

    alert("Note Saved");
  } // end store data function

  function getNotes() {
    toggleControls("on");
    var makeDiv = document.createElement('div');
    makeDiv.setAttribute("id", "items");
    var createList = document.createElement('ul');
    makeDiv.appendChild(createList) // puts createList into ul element created above 
    document.body.appendChild(makeDiv) // attach makeDiv to the document 
    $('items').style.display = "block";
    for(i=0, entries=localStorage.length; i<entries; i++) {
      var createLi = document.createElement('li');
      createList.appendChild(createLi);
      var key = localStorage.key(i);
      var value = localStorage.getItem(key);
      var savedNote = JSON.parse(value); // parse the save note object back into an object 
      var createSubList = document.createElement('ul');
      var createLi.appendChild(createSubList);
      for(a in savedNote) {
        var creatSubListItem = document.createElement('li');
        createSubList.appendChild(creatSubListItem)
        var subText = savedNote[a][0] + " " + savedNote[a][1];
        creatSubListItem.innerHTML = subText;
      } // end for in loop
    } // end for loop
  } // end getNotes function


  function clearNotes() {
    if(localStorage.length === 0){
      alert("Move along buddy, nothing here to clear.");
    } else {
      localStorage.clear()
      alert("All notes are deleted");
      window.location.reload();
      return false;
    } // end if 
  } // end clearNotes function


  // Variables defaults 
  var notesCategories = ["--Choose a Category--       ","Grocery","Fitness","Entertainment","Dining","Shopping","Sports"],
  favoriteValue = "No";
  makeCats();


  // Set links and submits click events 
  var displayLink = $('displayLink');
  displayLink.addEventListener("click", getNotes);
  var clearLink = $('clear');
  clearLink.addEventListener("click", clearNotes);
  var save = $('submit');
  save.addEventListener("click", saveNotes);


}) // end main function