改变 PropertyGrid 控件的编辑风格（1）——加入日期控件

张昱e-zhangyu@vip.sina.com

适用场合：

编辑日期类型数据

步骤一：定义从UITypeEditor 派生的类，示例如下：

using System;

using System.Windows.Forms;

using System.Drawing.Design;

using System.Windows.Forms.Design;

namespace blog.csdn.net.zhangyuk

{

     /// <summary>

     /// 在 PropertyGrid 上显示日期控件

     ///

     /// </summary>

     public class PropertyGridDateItem : UITypeEditor

     {

         MonthCalendar dateControl = new MonthCalendar();

         public PropertyGridDateItem()

         {

              dateControl.MaxSelectionCount = 1;

         }

         public override UITypeEditorEditStyle GetEditStyle(

System.ComponentModel.ITypeDescriptorContext context)

         {

              return UITypeEditorEditStyle.DropDown;

         }

         public override object EditValue(

System.ComponentModel.ITypeDescriptorContext context,

System.IServiceProvider provider,

object value)

         {      

              try

              {

                   IWindowsFormsEditorService edSvc = (IWindowsFormsEditorService)

provider.GetService(typeof(IWindowsFormsEditorService));

                   if( edSvc != null )

                   {

                       if( value is string )

                       {

                            dateControl.SelectionStart = DateTime.Parse( value as String );

                            edSvc.DropDownControl( dateControl );

                            return dateControl.SelectionStart.ToShortDateString();

                       }

                       else if( value is DateTime )

                       {

                            dateControl.SelectionStart = (DateTime)value;

                            edSvc.DropDownControl( dateControl );

                            return dateControl.SelectionStart;

                       }

                   }

              }

              catch( Exception ex )

              {

                   System.Console.WriteLine( "PropertyGridDateItem Error : " + ex.Message );

                   return value;

              }

              return value;

         }

     }

}

步骤二：编辑属性类，指定编辑属性。示例如下：

namespace blog.csdn.net.zhangyuk

{

         public class SomeProperties

     {

         private string _finished_time   = "";

                   ……

         [

Description("完成时间"),

              Category("属性"),

            EditorAttribute(typeof(PropertyGridDateItem),

typeof(System.Drawing.Design.UITypeEditor))

         ]

         public String 完成时间

         {

              get { return _finished_date; }

              set { _finished_date = value;}

         }

         ……

         }

}

步骤三：设置PropertyGrid的属性对象。示例如下：

         private void Form1_Load(object sender, System.EventArgs e)

         {

            this.propertyGrid1.SelectedObject = new SomeProperties();

         }