如何使用Vanilla Js拖放来存储拖放项目的状态？

element.ondragstart = function(event) {
  event.dataTransfer.setData("text/plain", event.target.id);
};

container.ondragover = function(event) {
  event.preventDefault();
};
container.ondrop = function(event) {
  event.preventDefault();
  var data = event.dataTransfer.getData("text/plain");
  var draggedElement = document.getElementById(data);
  container.appendChild(draggedElement);
};

container.ondrop = function(event) {
  event.preventDefault();
  var data = event.dataTransfer.getData("text/plain");
  var draggedElement = document.getElementById(data);
  container.appendChild(draggedElement);
  
  // 存储拖放项目的状态
  var projectState = {
    id: draggedElement.id,
    containerId: container.id
  };
  localStorage.setItem("projectState", JSON.stringify(projectState));
};

window.onload = function() {
  var projectState = localStorage.getItem("projectState");
  if (projectState) {
    projectState = JSON.parse(projectState);
    var draggedElement = document.getElementById(projectState.id);
    var container = document.getElementById(projectState.containerId);
    container.appendChild(draggedElement);
  }
};