Question

新问题和评论：

感谢大家的建议。我实际上从第二个线程调用了SetFreq（）。我需要两个线程。他们都在运行独立的任务。第二个线程通过Lru_Channel_Details类共享主线程的数据。我很难理解如何从第二个线程中的Lru_SetChanFreq类访问ChFreq数据成员。我更新了以下代码。我希望它能解释我想要做的事情。对不起，如果没有，我很乐意澄清。

再次感谢大家的推荐。

原始问题：

请原谅我，我是C＃和面向对象编程的新手。我无法访问其他班级成员。我创建了其他类对象来访问其成员字段。代码编译但我在显示它时没有得到任何结果。我找不到问题的答案是不成功的。有人可以告诉我我忽略了什么吗？下面是一段代码，说明了我的问题。

再次感谢您提出的任何建议。

    // this class I want to use the value of ChFreq from the Lru_SetChanFreq class to do some stuff for the Lru_operation class in the main thread to use
public class Lru_Channel_Details
{
    public void actualFreq()
    {
        Lru_operation LruOp2 = new Lru_operation(); // create main operations class object to access ChFreq     
        Lru_SetChanFreq LruSetChFreq1 = new Lru_SetChanFreq();  // (optional): create other class object to access ChFreq

        Console.WriteLine("LruOp2.SetChanFreq.ChFreq = {0}", LruOp2.SetChanFreq.ChFreq);  // fails to display the ChFreq value
        Console.WriteLine("LruSetChFreq1.ChFreq = {0}", LruSetChFreq1.ChFreq);      // (optional:) also fails to display the value
    }
}

// in this class, I have set the values of ChFreq to 405.0.  the call to do this came from the Lru_Listen class which runs in a 2ndary thread.
// this class then calls the actualFreq() from Lru_Channel_Details class.  The Lru_Channel_Details class is also accessed from the Lru_operation class,  
// which is running in the main thread. 
public class Lru_SetChanFreq
{
    private string chFreq;

    public string ChFreq
    {
        get { return chFreq; }
        set { chFreq = value; }
    }


    public void SetFreq()
    {
        Lru_operation LruOp1 = new Lru_operation();  // this object accesses multiple other classes 

        LruOp1.SetChanFreq.ChFreq = "405.0";    // assign this value using main operations class object

        LruOp1.ChanDet.actualFreq();    // calls another class method to use ChFreq

        // does stuff with LruOp1 to access other class methods (not shown)
    }
}


// this is where the program begins.  I'm running 2 threads concurrently and I need to share data between them.
[STAThread]
static void Main()
{   
    // starts a 2ndary thread to do stuff while the main thread is working.  
    Lru_Listen LruListen1 = new Lru_Listen();
    Thread LruListenThread = new Thread(new ThreadStart(LruListen1.ListenForAag));
    LruListenThread.Start();

    while(!LruListenThread.IsAlive);
    Thread.Sleep(1);

    Lru_operation LruOpX = new Lru_operation();         // create object to access Lru operation method
    LruOpX.LruOperation();



// this class is my main operations class.  it is running in the main thread.  the below objects are used to access other 
// class members.  it's main purpose is to take data from the Lru_Channel_Details class do some stuff on it and pass it to 
// another class.  it must be running in it's own thread. 
public class Lru_operation
{
    // this object is only used in other classes to access its class members.  it's not used in the main operations class
    public Lru_SetChanFreq SetChanFreq = new Lru_SetChanFreq();

    // this object is used in the main operations class to call methods from its class   
    public Lru_Channel_Details ChanDet = new Lru_Channel_Details();

    // does stuff with the above class objects' methods

}


// this class is running in a 2nd thread concurrently with the main thread.  it needs to share other class data with the main thread. 
// it's main purpose is to do some stuff to get data then call the SetFreq() from the Lru_SetChanFreq class 
public class Lru_Listen
{
    public void LruShowRequestData()
    {
        // do some other stuff      

        Lru_operation LruOp3 = new Lru_operation(); // create object to access set channel frequency method
        LruOp3.SetChanFreq.SetFreq();           // here is where SetFreq() from the Lru_SetChanFreq class is called
    }
}

Answer 1

你实际上从未调用过SetFreq（）方法，所以你永远不会有任何值。尝试在构造函数中设置它：

public Lru_SetChanFreq()
{
    this.SetFreq();
}

Answer 2

你永远不会设置ChFreq的值，所以它只是它的默认值，一个空字符串。

Lru_SetChanFreq LruSetChFreq1 = new Lru_SetChanFreq();

// this 
LruSetChFreq1.ChFreq = "new value";
// or this
LruSetChFreq1.SetFreq()

Console.WriteLine("LruSetChFreq1.ChFreq = {0}", LruSetChFreq1.ChFreq);

Answer 3

我看到两个问题：

您没有调用SetFreq，因此永远不会设置该值。您需要在SetFreq声明之前实际致电Console.WriteLine。
即使您正在调用它，SetFreq也会创建一个新的Lru_operation实例，该方法在方法运行时丢失，而不是仅仅将值分配给当前的实例。从SetFreq中删除三行代码，并将其替换为：chFreq = "405.0";

以下是修改代码以获得预期结果的方法。你刚才犯了一个简单的错误。

public void actualFreq()
{
    Lru_operation LruOp2 = new Lru_operation();
    Lru_SetChanFreq LruSetChFreq1 = new Lru_SetChanFreq();

    LruOp2.SetChanFreq.SetFreq();
    LruSetChFreq1.SetFreq();

    Console.WriteLine("LruOp2.SetChanFreq.ChFreq = {0}", LruOp2.SetChanFreq.ChFreq);
    Console.WriteLine("LruSetChFreq1.ChFreq = {0}", LruSetChFreq1.ChFreq);
}

如何在C＃中访问其他类成员

3 个答案: