Windows窗体应用程序，如何在自定义控件之间进行通信?

I have three user controls. Here are the description of them: 1) First user control(ucCountry) contains combobox which displays country names from an xml file.

我有三个用户控件。这里是它们的描述:1)First user control(ucCountry)包含combobox，它显示来自xml文件的国家名称。

2) Second user control(ucChannelType) contains two radio buttons one to select TV and other to select Radio Channel Type.

2)第二用户控制(ucChannelType)包含两个单选按钮，一个选择电视，另一个选择广播通道类型。

3) Third usercontrol(ucChannels) will populate all the channels where country name is provided by ucCountry and type provided by ucChannelType

3)第三个usercontrol(ucChannels)将填充ucCountry提供的所有通道，以及ucChannelType提供的类型

Now, how to communicate between these user control in a form. I need to decouple the usercontrols from the form. So, I need to use events. But if ucCountry fires an event (say CountryChanged event) and ucChannels subscribe the event, how to get the channel type from ucChannelType.

现在，如何在表单中这些用户控件之间进行通信。我需要将usercontrols与表单分离。我需要使用事件。但是如果ucCountry触发一个事件(比如CountryChanged事件)并ucChannels订阅该事件，那么如何从ucChannelType获取通道类型。

Thanks in advance...

提前谢谢…

3 个解决方案

#1

best solution is to add properties to your custom controls. there may be no fields in background, the getters will just get data from property of internal standard control.

最佳解决方案是向您的自定义控件添加属性。在后台可能没有字段，getter只会从内部标准控件的属性中获取数据。

#2

You could either have a property on ucCountry which provides the currently selected country. Something like:

您可以在ucCountry上拥有一个属性，该属性提供当前选择的国家。喜欢的东西:

public Country SelectedCountry
{
    get
    {
        return (Country) myComboBox.SelectedItem;
    }
}

And then when the event fires, the other controls go a get the property.

然后当事件触发时，其他控件去获取属性。

The other option is to use a custom event delegate, so the event handler for ucCountry.CountryChanged would have a country parameter:

另一个选项是使用自定义事件委托，即ucCountry的事件处理程序。CountryChanged有一个国家参数:

public delegate void CountryChangedDelegate(Country sender)

public event CountryChangedDelegate CountryChanged;

Event handler in ucChannels:

在ucChannels事件处理程序:

public void ucCountry_CountryChanged(Country sender)
{
    //do something with the new country
}

And wire the event to ucChannels:

并将事件连接到ucchannel:

myUcCountry.CountryChanged += new CountryChangedDelegate(ucCountry_CountryChanged);

#3

You need to have public properties for the controls supplying data, and a public method to register events to for the control consuming the data. Here's a quick example:

您需要为提供数据的控件提供公共属性，以及为使用数据的控件注册事件的公共方法。这里有一个简单的例子:

public static void Test()
{
    var a = new A();
    var b = new B();
    var c = new C() {a = a, b = b};
    a.OnChange += c.Changed;
    b.OnChange += c.Changed;
    a.State = "CA";
    b.ChannelType = "TV";
}

class A
{
    private string _state;

    public string State
    {
        get { return _state; }
        set
        {
            _state = value;
            if (OnChange != null) OnChange(this, EventArgs.Empty);
        }
    }

    public event EventHandler<EventArgs> OnChange;
}

class B
{
    private string _channelType;

    public string ChannelType
    {
        get { return _channelType; }
        set
        {
            _channelType = value;
            if (OnChange != null) OnChange(this, EventArgs.Empty);
        }
    }

    public event EventHandler<EventArgs> OnChange;
}

class C
{
    public A a { get; set; }
    public B b { get; set; }
    public void Changed(object sender, EventArgs e)
    {
        Console.WriteLine("State: {0}\tChannelType: {1}", a.State, b.ChannelType);
    }
}

#1