Question

我正在尝试将一个来自AJAX调用的字典单词列表放入我在JavaScript中定义的Dictionary对象中。我正在使用Google Closure Toolkit进行如下调用：

frankenstein.app.Dictionary = function(dictionaryUrl) {
  /** @private */ this._words = new goog.structs.Set();
  log("sending request");
  goog.net.XhrIo.send(dictionaryUrl, this.initDictionary);
}

frankenstein.app.Dictionary.prototype.initDictionary = function(e) {
    var xhr = e.target;
    this._words.addAll(xhr.getResponseText().split('\n'));
    log('Received dictionary file with ' + this._words.size());
}

不幸的是，在initDictionary方法内部，“this”指的是goog.net.XhrIo而不是Dictionary对象。有没有办法可以在initDictionary中将Dictionary对象引用为this？或者其他一些设置变量的方法？谢谢！

Answer 1

回调frankenstein.app.Dictionary.prototype.initDictionary可以绑定到frankenstein.app.Dictionary的实例，如下所示：

/** @constructor */
frankenstein.app.Dictionary = function(dictionaryUrl) {
  /** @private */ this._words = new goog.structs.Set();
  log("sending request");

  var xhr = new goog.net.XhrIo();
  goog.events.listenOnce(xhr, goog.net.EventType.COMPLETE, this.initDictionary,
      false /* capture phase */, this);
  xhr.send(dictionaryUrl);
};

frankenstein.app.Dictionary.prototype.initDictionary = function(e) {
  var xhr = /** @type {goog.net.XhrIo} */ (e.target);
  this._words.addAll(xhr.getResponseText().split('\n'));
  log('Received dictionary file with ' + this._words.size());
  xhr.dispose(); // Dispose of the XHR if it is not going to be reused.
};

goog.events.listenOnce的第五个参数（或者goog.events.listen）是一个可选对象，其范围将调用侦听器。

使用XhrIo填充Object的变量

1 个答案: