所以我从来没有通过在面板中嵌套可编辑控件并对接它来解决这个问题，而是通过不同的方法来解决这个问题。我在User Control OnLoad事件中手动定位控件，并通过可编辑控件上的锚属性处理UC大小调整。在我的示例中，我将其定位在顶部页眉的正下方，并将锚设置为左、上、右和下（这样它就可以与控件一起拉伸）。
但是，您还需要防止用户将控件拖动到UC的不可编辑区域，并且还必须阻止用户调整可编辑控件的大小或移动可编辑控件。这是通过下面的代码实现的：

[Designer(typeof(WizardDesigner))]
public partial class Wizard : BaseUserControl
{
    [Browsable(false)]
    [DesignerSerializationVisibility(DesignerSerializationVisibility.Content)]
    public WizardPageControl WizardPageControlArea
    {
        get { return wizardPageControl; }
    }

    public Wizard()
    {
        InitializeComponent();
    }
    
    private void Wizard_Load(object sender, EventArgs e)
    {
        wizardPageControl.Location = new Point(0, TopPN.Height);
        wizardPageControl.Size = new Size(this.Width, this.Height - TopPN.Height - BottomPN.Height);
    }   
}

internal class WizardDesigner : ParentControlDesigner
{

    public override void Initialize(System.ComponentModel.IComponent component)
    {
        base.Initialize(component);
        var uc = (Wizard)component;
        EnableDesignMode(uc.WizardPageControlArea, "WizardPageControlArea");            
    }
    
    // prevents dropping of controls onto non-Design-mode enabled areas
    protected override void OnDragOver(DragEventArgs de)
    {
        de.Effect = DragDropEffects.None;
    }
    
    protected override IComponent[] CreateToolCore(ToolboxItem tool, int x,
            int y, int width, int height, bool hasLocation, bool hasSize)
    {
        return null;
    }   
}

[Designer(typeof(Designers.WizardPageControlDesigner))]
public class WizardPageControl: UIElements.TabControl
{
    public WizardPageControl()
    {
    }
}

internal class WizardPageControlDesigner : ParentControlDesigner
{
    // Prevents user from resizing or moving the editable control
    public override SelectionRules SelectionRules
    {
        get
        {
            SelectionRules selectionRules = base.SelectionRules;
            selectionRules &= ~SelectionRules.AllSizeable;
            selectionRules &= ~SelectionRules.Moveable;
            return selectionRules;
        }
    }
    
    // Hides other properties from user which may chnage the positoning of the control
    protected override void PostFilterProperties(IDictionary properties)
    {
        base.PostFilterProperties(properties);
        var propertiesToRemove = new string[]
            {
                "Dock", "Anchor", "Size", "Location", "Width", "Height",
                "MinimumSize", "MaximumSize", "AutoSize", "AutoSizeMode",
                "Visible", "Enabled","DrawMode","HideBorders","HideTabs"
            };
        foreach (var item in propertiesToRemove)
        {
            if (properties.Contains(item))
                properties[item] = TypeDescriptor.CreateProperty(this.Component.GetType(),
                    (PropertyDescriptor)properties[item],
                    new BrowsableAttribute(false));
        }
    }
}

希望它能拯救我生命中失去的两天！🙂