PropertyGrid 验证

Question

我有一个PropertyGrid。当我输入格式错误的值（即 - 将字符串转换为整数项）时，我收到一条错误消息。如果我单击“确定”，则错误值会一直存在，直到我更改它为止。如果我点击“取消”，就会恢复原来的值。

我想控制按钮，因此单击“确定”也会将原始值设置回来，而不是像取消按钮那样显示错误的值。

我该怎么做？

Answer 1

我将加入 @Crono 的行列，你为什么想要你想要的？

如果你问我怎样才能删除那个对话框，那么我可以回答使用自己的TypeConverter：

public class IntConverter : TypeConverter
{
    public override bool CanConvertFrom(ITypeDescriptorContext context, Type sourceType)
    {
        return true;
    }

    public override bool CanConvertTo(ITypeDescriptorContext context, Type destinationType)
    {
        return true;
    }

    public override object ConvertFrom(ITypeDescriptorContext context, System.Globalization.CultureInfo culture, object value)
    {
        if(value is string)
        {
            // try parse to int, do not throw exception
        }
        return 0; // always return something
    }

    public override object ConvertTo(ITypeDescriptorContext context, System.Globalization.CultureInfo culture, object value, Type destinationType)
    {
        if (destinationType == typeof(string))
            return value.ToString();
        return base.ConvertTo(context, culture, value, destinationType); // i left it here but it should never call it
    }
}

如果你问我想要我自己的对话框来编辑一些东西，那么我会回答使用自己的 UITypeEditor：

public class MyEditor : UITypeEditor
{

    public override UITypeEditorEditStyle GetEditStyle(ITypeDescriptorContext context)
    {
        return UITypeEditorEditStyle.Modal;
    }

    public override object EditValue(ITypeDescriptorContext context, IServiceProvider provider, object value)
    {
        Form1 form1 = new Form1();
        form1.ShowDialog();
        return form1.SomeProperty;
    }
}

而用法是

[TypeConverter(typeof(IntConverter))]
[EditorAttribute(typeof(MyEditor), typeof(UITypeEditor))]
public int SomeProperty
{
    ...
}

但是您想要那个错误对话框（当设置/获取属性时出现异常时显示）并且您希望 Ok 按钮的工作方式与 Cancel 相同。为什么？

Answer 2

简短的回答是：你不能。属性网格不支持修改此项。

但是，如果您心情不好，这里有一些示例代码演示了如何使用此对话框。当然，使用这一切需要您自担风险。

如何使用这个实用程序类：

propertyGrid1.Site = new MySite(propertyGrid1);
propertyGrid1.SelectedObject = MyObj;

实用类代码：

public class MySite : ISite, IUIService
{
    public MySite(PropertyGrid propertyGrid)
    {
        PropertyGrid = propertyGrid;
    }

    public object GetService(Type serviceType)
    {
        if (serviceType == typeof(IUIService))
            return this;

        return null;
    }

    // this is part of IUIService
    public DialogResult ShowDialog(Form form)
    {
        // Check the form passed here is the error dialog box.
        // It's type name should be GridErrorDlg.
        // You can also scan all controls and for example
        // remove or modify some buttons...
        DialogResult result = form.ShowDialog(PropertyGrid);
        if (form.GetType().Name == "GridErrorDlg" && result == DialogResult.OK)
        {
            PropertyGrid.Refresh();
        }
        return result;
    }

    public PropertyGrid PropertyGrid { get; private set; }
    public bool DesignMode { get { return false; } }
    public IContainer Container { get { return null; } }
    public bool CanShowComponentEditor(object component) { return false; }

    // I've left the rest as not implemented, but make sure the whole thing works in your context...
    public IComponent Component
    {
        get { throw new NotImplementedException(); }
    }

    public string Name
    {
        get
        {
            throw new NotImplementedException();
        }
        set
        {
            throw new NotImplementedException();
        }
    }

    public IWin32Window GetDialogOwnerWindow()
    {
        throw new NotImplementedException();
    }

    public void SetUIDirty()
    {
        throw new NotImplementedException();
    }

    public bool ShowComponentEditor(object component, IWin32Window parent)
    {
        throw new NotImplementedException();
    }

    public void ShowError(Exception ex, string message)
    {
        throw new NotImplementedException();
    }

    public void ShowError(Exception ex)
    {
        throw new NotImplementedException();
    }

    public void ShowError(string message)
    {
        throw new NotImplementedException();
    }

    public DialogResult ShowMessage(string message, string caption, MessageBoxButtons buttons)
    {
        throw new NotImplementedException();
    }

    public void ShowMessage(string message, string caption)
    {
        throw new NotImplementedException();
    }

    public void ShowMessage(string message)
    {
        throw new NotImplementedException();
    }

    public bool ShowToolWindow(Guid toolWindow)
    {
        throw new NotImplementedException();
    }

    public System.Collections.IDictionary Styles
    {
        get { throw new NotImplementedException(); }
    }
}