Question

我创建了一个UserControl，上面有一个FlowLayoutPanel。我在运行时使用PictureBoxes的CollectionBase填充此面板。然后我在我的WindowsForm上有一个FlowLayoutPanel，我在运行时使用UserControls的CollectionBase填充。

现在，我希望能够访问UserControl中的自定义函数，以便将另一个PictureBox添加到instanciated（现有）UserControl的FlowLayoutPanel。如何访问该功能？

该功能在UserControl中是公共的，但是我无法通过CollectionBase来使用它。

以下是UserControl的代码：

public partial class UserDisplay : UserControl
{
    public UserDisplay()
    {
        InitializeComponent();
        myEquipArray = new ImageArray(flpnlTools);
    }
    public void AddEquip(string EquipName, Image EquipImage)
    {
        myEquipArray.AddNewEquip(EquipName, EquipImage);
    }
    //Accessor
    public ControlCollection Equips
    {
        get
        {
            return flpnlEquips.Controls;
        }
    }
}
public class ImageArray : System.Collections.CollectionBase
{
    private readonly System.Windows.Forms.FlowLayoutPanel HostPanel;

    public ImageArray(FlowLayoutPanel hostPanel)
    {
        HostPanel = hostPanel;
    }

    public System.Windows.Forms.PictureBox AddNewEquip(string EquipName, Image EquipImage)
    {
        PictureBox pbA = new PictureBox();
        this.List.Add(pbA);
        HostPanel.Controls.Add(pbA);
        pbA.Tag = EquipName;
        pbA.Image = EquipImage;

        return pbA;
    }

    public void RemoveEquip(string EquipName)
    {
        if (this.Count > 0)
        {
            int i = 0;
            while (EquipName != HostPanel.Controls[i].Tag.ToString())
            {
                i++;
            } 
            HostPanel.Controls.Remove(this[EquipName]);
            this.List.RemoveAt(i);
        }
    }

    public PictureBox this[string EquipName]
    {
        get
        {
            int i = 0;
            while (EquipName != HostPanel.Controls[i].Tag.ToString())
            {
                i++;
            }
            return (PictureBox)this.List[i];
        }
    }
}

我使用此类在我的WindowsForm上实现UserConrol：

public class UserDsp : System.Collections.CollectionBase
    {
        private readonly System.Windows.Forms.FlowLayoutPanel HostPanel;

        public DisplayControl.UserDisplay AddNewUser(Int64 UserID, string UserName, Image UserImage, string EquipName, Image EquipImage)
        {
            DisplayControl.UserDisplay newUser = new DisplayControl.UserDisplay();
            this.List.Add(newUser);
            HostPanel.Controls.Add(newUser);
            newUser.Tag = UserID;
            newUser.UserName = UserName;
            newUser.UserImage = UserImage;
            newUser.AddEquip(EquipName, EquipImage);  //THIS ADDS THE PICTUREBOX CORRECTLY

            return newUser;
        }

        public void AddNewEquip(Int64 UserID, Int64 EquipID, string EquipName, Image EquipImage)
        {
            if (this.Count > 0)
            {
                int i = 0;
                while (UserID != Convert.ToInt64(HostPanel.Controls[i].Tag))
                {
                    i++;
                }
                //  Found the Control with UserID
                HostPanel.Controls[i].AddEquip(EquipName, EquipImage);  //THIS DOES NOT WORK
            }
        }

        public UserDsp(System.Windows.Forms.FlowLayoutPanel hostPanel)
        {
            HostPanel = hostPanel;
        }

        public void RemoveUser(Int64 UserID)
        {
            if (this.Count > 0)
            {
                int i = 0;
                while (UserID != Convert.ToInt64(HostPanel.Controls[i].Tag))
                {
                    i++;
                }
                HostPanel.Controls.Remove(this[UserID]);
                this.List.RemoveAt(i);
            }
            UsersLogdIn.Remove(UserID);
        }

        public DisplayControl.UserDisplay this[Int64 UserID]
        {
            get
            {
                int i = 0;
                while (UserID != Convert.ToInt64(HostPanel.Controls[i].Tag))
                {
                    i++;
                }
                return (DisplayControl.UserDisplay)this.List[i];
            }
        }

        public List<long> usersLogdIn
        {
            get
            {
                return UsersLogdIn;
            }
        }
    }
}

在这段代码中，我可以在实例化Control时在Control的FlowLayoutPanel中创建一个新的PictureBox：

            newUser.AddEquip(EquipName, EquipImage);  //THIS ADDS THE PICTUREBOX CORRECTLY

但是当我尝试通过CollectionBase访问它时：

        public void AddNewEquip(Int64 UserID, Int64 EquipID, string EquipName, Image EquipImage)
        {
            if (this.Count > 0)
            {
                int i = 0;
                while (UserID != Convert.ToInt64(HostPanel.Controls[i].Tag))
                {
                    i++;
                }
                //  Found the Control with UserID
                HostPanel.Controls[i].AddEquip(EquipName, EquipImage);  //THIS DOES NOT WORK
            }
        }

我也尝试将控件拉出来：

        public void AddNewEquip(Int64 UserID, Int64 EquipID, string EquipName, Image EquipImage)
        {
            if (this.Count > 0)
            {
                int i = 0;
                while (UserID != Convert.ToInt64(HostPanel.Controls[i].Tag))
                {
                    i++;
                }
                //  Found the Control with UserID
                UserDisplay newUserDisplay = HostPanel.Controls[i] as UserDisplay  //THIS DOES NOT WORK
            }
        }

我到处都寻求帮助，但没有发现任何相关内容。请帮助！

谢谢。

Answer 1

我在一些外界的帮助下想出来了。

基本上我需要将控件强制转换为UserDisplay。我不知道为什么当我使用以下方法将其取出时它不起作用：

UserDisplay newUserDisplay = HostPanel.Controls[i] as UserDisplay

但我改用了这段代码：

(HostPanel.Controls[i] as UserDisplay).AddEquip(EquipName, EquipImage);

在我以这种方式声明之前，我确实确保控件是正确的类型：

if (HostPanel.Controls[i] is UserDisplay)

感谢您的帮助。

如何访问存储在System.Collections.CollectionBase中的UserControl中的方法？

1 个答案: