Question

当我将数据保存到localstorage时，我需要增加键值，因为当我单击按钮键对所有记录都相同并且记录只是更新时，不会创建新的。我知道我可以使用闭包装来做这件事，我在JS中很新鲜并且不知道如何做到这一点。

(function() {

window.onload = function() {
    document.getElementById('buttonCreate').onclick = function() {
        var topicValue = document.getElementById("create-topic").value;
        var statusValue = document.getElementById("create-status").value;
        var descriptionValue = document.getElementById("create-description").value;
        var key = 0;
        var storage = new Storage();
        var ticket = {
            topic: topicValue,
            status: statusValue,
            description: descriptionValue
        };
        storage.set(key, ticket);
        return (function() {
            key++;
            return key;

        }());
    }
}

})();

function Storage() {
  this._ITEMS_DESCRIPTOR = 'items';
}
Storage.prototype.get = function() {
  var fromStorage = localStorage.getItem(this._ITEMS_DESCRIPTOR);
  return fromStorage ? JSON.parse(fromStorage) : [];
};
Storage.prototype.set = function(key, items) {
  localStorage.setItem(key, JSON.stringify(items));
};

Answer 1

您需要在函数前声明变量，以保存值并添加1 +。

    (function() {

  window.onload = function() {
    var key = 0; //move var key to here
    document.getElementById('buttonCreate').onclick = function() {
      var topicValue = document.getElementById("create-topic").value;
      var statusValue = document.getElementById("create-status").value;
      var descriptionValue = document.getElementById("create-description").value;
      // var key = 0; remove these line
      var storage = new Storage();
      var ticket = {
        topic: topicValue,
        status: statusValue,
        description: descriptionValue
      };
      storage.set(key, ticket);
      return (function() {
        key++;
        return key;

      }());
    }
  }

})();

增加键值以在localstorage

1 个答案: