从“形式”具有参数继承 [英] Inherit from a 'Form' which has parameters

问题描述

我有一个名为 ScanFolder 表格，我需要另一种形式，需要非常类似于 ScanFolder ，所以我决定用形式继承。但是，似乎与构造一些误解。

I have a Form named ScanFolder, and I need another Form, that needs to be very similar to ScanFolder, so I decided to use form inheritance. But there seems to be some misunderstanding with the constructor.

ScanFolder 是这样的：

public partial class ScanFolder : Form
{
    public ScanFolder(MainForm parent, bool[] autoModes, GlobalMethods GMethodsClass)
    {
        //Doing something with parameters
    }
}

我想继承表格是这样的：

public partial class Arch2 : ScanFolder
{
}

但我得到警告构造上键入mhmm.ScanFolder没有找到，也没有对 Arch2错误表格编辑模式，在这里我看到调用堆栈错误

But I get warning Constructor on type 'mhmm.ScanFolder' not found, and also there is an error on Arch2 Form edit mode, where I see a call stack error.

所以，我想是这样的：

public partial class Arch2 : ScanFolder
{
    public Arch2(MainForm parent, bool[] autoModes, GlobalMethods GMethodsClass)
        : base(parent, autoModes, GMethodsClass)
    {
    }
}

但它仍是相同的。

But it is still the same.

正如你所看到的，我明明没有任何想法，我在做什么。我试图做到的，是让 Arch2 看起来一样的 ScanFolder ，这样我就可以看到它的设计师视图，还覆盖某些方法或事件处理程序。

As you can see, I clearly don't have any idea what I'm doing. What I'm trying to achieve is getting Arch2 to look the same as ScanFolder, so I can see it in designer view and also override some methods or event handlers.

推荐答案

要使用窗体设计器，你将需要有一个参数的构造函数：

To use the Forms designer, you will need to have a parameterless constructor:

public partial class ScanFolder : Form
{
    public ScanFolder()
    {
         InitializeComponent(); // added by VS
    }

    public ScanFolder(MainForm parent, bool[] autoModes, GlobalMethods gm)
       : this() // <-- important
    {
         // don't forget to call the parameterless ctor in each
         // of your ctor overloads
    }
}

或者，如果你真的需要有一些初始化参数，你可以做到这一点的其他方式：

Or, if you really need to have some init params, you can do it the other way around:

public partial class ScanFolder : Form
{
    public ScanFolder()
        : this(null, new bool[0], new GlobalMethods())
    {

    }

    public ScanFolder(MainForm parent, bool[] autoModes, GlobalMethods gm)
    {
        InitializeComponent(); // added by VS
        // other stuff
    }
}

我推荐的第一种方法，否则你需要通过一些合理的默认参数（我不建议传递一个空参数）。

I recommend the first approach, otherwise you need to pass some reasonable default parameters (I don't recommend passing a null parameter).

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