Javascript 如何使用继承引用基变量
我一直在尝试许多方法来实现这一目标,但都没有成功。有人能帮我吗 基本对象:Javascript 如何使用继承引用基变量,javascript,jquery,inheritance,prototypal-inheritance,Javascript,Jquery,Inheritance,Prototypal Inheritance,我一直在尝试许多方法来实现这一目标,但都没有成功。有人能帮我吗 基本对象: var Recorder = function (source) { this.context = source.context; var recording = null; this.start = function () { recording = true; } this.stop = function () { recording = f
var Recorder = function (source) {
this.context = source.context;
var recording = null;
this.start = function () {
recording = true;
}
this.stop = function () {
recording = false;
}
}
派生对象:
var messageRecorder = function () {
this.isRecording = function () {
return this.recording;
}
}
所以我有一个基本对象,Recorder,它有一个变量'recording'。我想要一个扩展/派生对象messageRecorder,它可以返回'recording'的值(来自Recorder)。有什么建议吗?我尝试了jQuery扩展,var audioRecorder=$.extend({},new Recorder(),new messageRecorder()),但没有成功。我还尝试修改messageRecording,如下所示:
var messageRecorder = function () {
Recorder.apple(this, arguments);
this.isRecording = function () {
return this.recording; //declared in Recorder
}
}
并像这样实例化:var audioRecorder=newmessagerecorder(source)
在我两次失败的尝试中,当我调用audioRecorder.start()时,它工作正常。调用audioRecorder.isRecording()时,变量“recording”未定义,可能是因为我没有尝试正确访问它。有什么建议吗?您可以通过对正在创建的对象调用父构造函数来处理简单继承,因此可以执行以下操作:
var Recorder = function (source) {
this.context = source.context;
this.recording = null;
this.start = function () {
this.recording = true;
};
this.stop = function () {
this.recording = false;
};
};
var messageRecorder = function() {
Recorder.apply(this, arguments);
this.isRecording = function() {
return this.recording;
};
};
var src = {
context: 'something'
};
var audioRecorder = new messageRecorder(src);
audioRecorder.start();
console.log("recording? " + audioRecorder.isRecording());
audioRecorder.stop();
console.log("recording? " + audioRecorder.isRecording());
这将为您提供以下输出(正确设置this.recording
):
您可以通过对正在创建的对象调用父构造函数来处理简单继承,因此可以执行以下操作:
var Recorder = function (source) {
this.context = source.context;
this.recording = null;
this.start = function () {
this.recording = true;
};
this.stop = function () {
this.recording = false;
};
};
var messageRecorder = function() {
Recorder.apply(this, arguments);
this.isRecording = function() {
return this.recording;
};
};
var src = {
context: 'something'
};
var audioRecorder = new messageRecorder(src);
audioRecorder.start();
console.log("recording? " + audioRecorder.isRecording());
audioRecorder.stop();
console.log("recording? " + audioRecorder.isRecording());
这将为您提供以下输出(正确设置this.recording
):
录制
是一项重要功能。您绝对不能在记录器
之外访问它。录制
是一种功能。您绝对不能在记录器
之外访问它。