没有默认构造函数的设计 [英] Design without default constructor

问题描述

我想使用默认构造函数来限制创建对象。因为我有如下的想法：

I want to restrict creating object using default constructor. Because I have a desing like below:

class Program
{
    static void Main(string[] args)
    {
        BaseClass bc = new BaseClass("","");
        XmlSerializer xml = new XmlSerializer(typeof(BaseClass));
        StreamWriter sw = new StreamWriter(File.Create("c:\\test.txt"));
        xml.Serialize(sw,bc);
        sw.Flush();
        sw.Close();
    }
}
[Serializable]
public class BaseClass
{
    public string UserName, Password;
    // I don't want to create default constructor because of Authentication
    public BaseClass(string _UserName, string _Password)
    {
        UserName = _UserName;
        Password = _Password;
        f_Authenticate();
    }
    private void f_Authenticate() { }
}

public class DerivedClass:BaseClass
{
    public DerivedClass(string _UserName, string _Password) : base(_UserName, _Password)
    {
    }
}

没关系但是当我将BaseClass设置为Serializable时，会产生以下错误：
未处理的异常：System.InvalidOperationException：ConsoleApplication1.BaseC
lass无法序列化，因为它没有无参数的构造函数

This is ok. But when I make BaseClass to Serializable it'll generate this error: Unhandled Exception: System.InvalidOperationException: ConsoleApplication1.BaseC lass cannot be serialized because it does not have a parameterless constructor.

现在我的设计正在崩溃，因为我需要有用户名，密码参数，但默认构造函数会破坏我的设计....

Now my design is collapsing because I need to have Username, Password parameters but default constructor is ruining my design....

我该怎么办？

推荐答案

创建一个私有的默认构造函数

Create a private default constructor

private DerivedClass()
{
    // code
}

串行器即使它是私人的

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