3

可能重复：
有条件的“可浏览”属性

我定义AppSettings了具有一些属性的类。在我的表单中，当 I 时click Button1，我想显示属性 1 和 2（显示 1,2，隐藏或不显示其他属性），当 时click Button2，我想显示属性 2 和 3（1 是隐藏，2,3 是显示，其他属性隐藏或不显示），我该怎么做？

public class AppSettings
{
    [BrowsableAttribute(true), CategoryAttribute("Document Settings"), DefaultValueAttribute(true)]
    public bool SaveOnClose{ get; set; }

    [BrowsableAttribute(true), CategoryAttribute("Global Settings"), ReadOnlyAttribute(true), DefaultValueAttribute("Welcome to AppDev!")]
    public string GreetingText { get; set; }

    [BrowsableAttribute(true), DescriptionAttribute("The rate in milliseconds that the text will repeat."), CategoryAttribute("Global Settings"), DefaultValueAttribute(10)]
    public int MaxRepeatRate { get; set; }

    [BrowsableAttribute(true), CategoryAttribute("Global Settings"), DefaultValueAttribute(4)]
    public int ItemsInMRUList { get; set; }

    [BrowsableAttribute(true), DefaultValueAttribute(false)]
    public bool SettingsChanged { get; set; }

    [BrowsableAttribute(true), CategoryAttribute("Version"), DefaultValueAttribute("1.0"), ReadOnlyAttribute(true)]
    public string AppVersion { get; set; }
}

我想动态更改BrowseAttribute为真或假。我该怎么做 ？

表格代码是：

AppSettings AppSet = new AppSettings();

AppSet.AppVersion = "2.3";
AppSet.SaveOnClose = true;
AppSet.GreetingText = "Welcome to Dar!";
AppSet.ItemsInMRUList = 4;
AppSet.MaxRepeatRate = 10;
AppSet.SettingsChanged = false;

...

propertyGrid1.SelectedObject = AppSet;

此更改有错误：

public static bool state = true;
BrowsableAttribute(state)

错误：

属性参数必须是属性参数类型的常量表达式、typeof 表达式或数组创建表达式

4

1 回答 1

6

对于过滤，我只会更改BrowsableAttributes. PropertyGrid在下文中，我：

  • 定义一个自定义属性 ，[DisplayMode(...)]它描述什么时候应该可见
    • 覆盖IsMatch以指示何时应将属性视为等效
  • AppSettings用属性装饰你的类型的一些设置, ,
  • 更改BrowsableAttributes网格上的 ，指定特定的DisplayModeAttribute，并显示
  • 重复启用不同的设置

这是代码：

using System.ComponentModel;
using System;
using System.Windows.Forms;

[AttributeUsage(AttributeTargets.Property, AllowMultiple = false, Inherited = true)]
public class DisplayModeAttribute : Attribute
{
    private readonly string mode;
    public DisplayModeAttribute(string mode)
    {
        this.mode = mode ?? "";
    }
    public override bool Match(object obj)
    {
        var other = obj as DisplayModeAttribute;
        if (other == null) return false;

        if (other.mode == mode) return true;

        // allow for a comma-separated match, in either direction
        if (mode.IndexOf(',') >= 0)
        {
            string[] tokens = mode.Split(',');
            if (Array.IndexOf(tokens, other.mode) >= 0) return true;
        }
        else if (other.mode.IndexOf(',') >= 0)
        {
            string[] tokens = other.mode.Split(',');
            if (Array.IndexOf(tokens, mode) >= 0) return true;
        }
        return false;
    }
}

public class AppSettings
{
    [DisplayMode("A"), CategoryAttribute("Document Settings"), DefaultValueAttribute(true)]
    public bool SaveOnClose { get; set; }

    [DisplayMode("A,B")]
    [CategoryAttribute("Global Settings"), ReadOnlyAttribute(true), DefaultValueAttribute("Welcome to AppDev!")]
    public string GreetingText { get; set; }

    [DisplayMode("B"), BrowsableAttribute(true), DescriptionAttribute("The rate in milliseconds that the text will repeat."), CategoryAttribute("Global Settings"), DefaultValueAttribute(10)]
    public int MaxRepeatRate { get; set; }

    [BrowsableAttribute(true), CategoryAttribute("Global Settings"), DefaultValueAttribute(4)]
    public int ItemsInMRUList { get; set; }

    [BrowsableAttribute(true), DefaultValueAttribute(false)]
    public bool SettingsChanged { get; set; }

    [BrowsableAttribute(true), CategoryAttribute("Version"), DefaultValueAttribute("1.0"), ReadOnlyAttribute(true)]
    public string AppVersion { get; set; }
}
static class Program
{
    [STAThread]
    static void Main()
    {
        using (var form = new Form())
        using (var grid = new PropertyGrid())
        {
            grid.Dock = DockStyle.Fill;
            grid.SelectedObject = new AppSettings();
            grid.BrowsableAttributes = new AttributeCollection(
                new DisplayModeAttribute("A"));
            form.Controls.Add(grid);
            form.ShowDialog();

            grid.BrowsableAttributes = new AttributeCollection(
                new DisplayModeAttribute("B"));
            form.ShowDialog();
        }
    }
}
于 2012-08-22T19:11:06.103 回答