PropertyGrid使用小记

PropertyGrid进行编辑的时候，还是比较方便的，至少不进行界面布局了，目前在一个小工具中需要实现下面的效果

数据库类型是enum

需要实现一个Convert类，基类是ExpandableObjectConverter

重写基类的CanConvertFrom,CanConvertTo,ConvertFrom,ConvertTo方法即可实现

  Public Class DBInfoConverter
        Inherits ExpandableObjectConverter

        Public Overrides Function CanConvertFrom(ByVal context As System.ComponentModel.ITypeDescriptorContext, _

 ByVal sourceType As System.Type) As Boolean
            If sourceType Is GetType(String) Then
                Return True
            End If
            Return MyBase.CanConvertFrom(context, sourceType)
        End Function

      

        Public Overrides Function CanConvertTo(ByVal context As System.ComponentModel.ITypeDescriptorContext, ByVal destinationType As System.Type) As Boolean
            If destinationType Is GetType(String) Then
                Return True
            End If
            Return MyBase.CanConvertTo(context, destinationType)
        End Function


        Public Overrides Function ConvertFrom(ByVal context As System.ComponentModel.ITypeDescriptorContext,  _

　　ByVal culture As System.Globalization.CultureInfo, ByVal value As Object) As Object

            Dim db As New DBInfo
            If TypeOf value Is String Then
                Dim str As String = value.ToString

                Dim chars() As String = str.Split(","c)
                If chars.Length <> 5 Then
                    Throw New ArgumentException("无效的值", "value")
                End If

                Dim stringTypeConvert = TypeDescriptor.GetConverter(GetType(String))
                Dim enumTypeConvert = TypeDescriptor.GetConverter(GetType(DBInfoType))
                db.服务器地址 = stringTypeConvert.ConvertToString(context, culture, chars(0))
                db.用户名 = stringTypeConvert.ConvertToString(context, culture, chars(1))
                db.密码 = stringTypeConvert.ConvertToString(context, culture, chars(2))
                db.数据库 = stringTypeConvert.ConvertToString(context, culture, chars(3))
                db.数据库类型 = CType(enumTypeConvert.ConvertFrom(chars(4)), DBInfoType)

            End If

            Return db
        End Function


        Public Overrides Function ConvertTo(ByVal context As System.ComponentModel.ITypeDescriptorContext, ByVal culture As System.Globalization.CultureInfo, _

　　　　　　 ByVal value As Object, ByVal destinationType As System.Type) As Object


            If value Is Nothing Then

                value = New DBInfo
                'Return MyBase.ConvertTo(context, culture, value, destinationType)
            End If

            If Not TypeOf value Is DBInfo Then
                Throw New ArgumentException("无效的对象", "value")
            End If

            Dim db = CType(value, DBInfo)

            Dim stringTypeConvert = TypeDescriptor.GetConverter(GetType(String))
            Dim enumTypeConvert = TypeDescriptor.GetConverter(GetType(DBInfoType))
            Dim chars() As String = {stringTypeConvert.ConvertToString(context, culture, db.服务器地址), _
                                     stringTypeConvert.ConvertToString(context, culture, db.用户名), _
                                     stringTypeConvert.ConvertToString(context, culture, db.密码), _
                                     stringTypeConvert.ConvertToString(context, culture, db.数据库), _
                                      CStr(enumTypeConvert.ConvertTo(db.数据库类型, GetType(String)))}
            Return String.Join(culture.TextInfo.ListSeparator, chars)
        End Function

    End Class

相关资料：

http://msdn.microsoft.com/zh-cn/library/ayybcxe5.aspx

http://msdn.microsoft.com/zh-cn/library/system.componentmodel.notifyparentpropertyattribute.aspx

http://www.cnblogs.com/wmj/archive/2008/05/16/1199823.html

http://msdn.microsoft.com/zh-tw/vcsharp/system.componentmodel.enumconverter(zh-cn).aspx