C# 主窗体引用异常

Question

我做了一个 UserControl 并想添加 MainForm Reference

  public partial class ConsolePage : UserControl

{

    public synForm mainForm = new synForm();

    public ConsolePage(synForm parentForm)

    {

        mainForm = parentForm();

        InitializeComponent();

    }

所以，问题是，只要我在 c# 代码中创建我的 UserControl（无论在哪里），它都可以完美运行，但是当我尝试从 Toolbox 的 Designer 中添加他时，我得到了一个异常。

我知道，我应该这样称呼他们

MyControl whatever = new MyControl(this); 

我知道如果我想从 Toolbox 添加 myControl ，我应该在我的 Form.Designer 中更正它！

不要恨我，我是编程和拼写的新手 :D

编辑：<<<<<<<

忘了说我得到了什么错误：

System.ComponentModel.Design.Serialization.DesignerSerializationManager.CreateInstance（类型类型，ICollection 参数，字符串名称，布尔型 addToContainer）

System.ComponentModel.Design.Serialization.DesignerSerializationManager.System.ComponentModel.Design.Serialization.IDesignerSerializationManager.CreateInstance（类型类型，ICollection 参数，字符串名称，布尔型 addToContainer）

System.ComponentModel.Design.Serialization.CodeDomSerializerBase.DeserializeInstance(IDesignerSerializationManager manager, Type type, Object[] parameters, String name, Boolean addToContainer)

System.ComponentModel.Design.Serialization.ComponentCodeDomSerializer.DeserializeInstance(IDesignerSerializationManager manager, Type type, Object[] parameters, String name, Boolean addToContainer)

System.ComponentModel.Design.Serialization.CodeDomSerializerBase.DeserializeExpression(IDesignerSerializationManager manager, String name, CodeExpression expression)

System.ComponentModel.Design.Serialization.CodeDomSerializer.DeserializeStatementToInstance(IDesignerSerializationManager manager, CodeStatement statement)

 System.ComponentModel.Design.Serialization.CodeDomSerializer.Deserialize(IDesignerSerializationManager manager, Object codeObject)

bei System.Windows.Forms.Design.ControlCodeDomSerializer.Deserialize(IDesignerSerializationManager manager, Object codeObject)

System.ComponentModel.Design.Serialization.TypeCodeDomSerializer.DeserializeName(IDesignerSerializationManager manager, String name, CodeStatementCollection statements) 

Answer 1

在不知道错误消息（您只提供堆栈跟踪）和 parentForm() 的内容的情况下，说起来并不容易。但似乎 parentForm() 正在做一些在设计器中不可能的事情。因此，您可以通过检查 DesignMode ( https://docs.microsoft.com/en-us/dotnet/api/system.componentmodel.component.designmode?redirectedfrom=MSDN&view=netframework-4.7 .2#System_ComponentModel_Component_DesignMode）。public ConsolePage()&nbsp; &nbsp; {&nbsp; &nbsp; &nbsp; &nbsp; if (!DesignMode)&nbsp; &nbsp; &nbsp; &nbsp; {&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; mainForm = parentForm();&nbsp; &nbsp; &nbsp; &nbsp; }&nbsp; &nbsp; &nbsp; &nbsp; InitializeComponent();&nbsp; &nbsp; }