如何在datagridview中将类属性指定为显示数据成员 [英] How to assign class property as display data member in datagridview

问题描述

我想在datagridview中显示我的数据。我创建了一个具有不同属性的类，并使用它的列表作为数据源。它工作正常。但我很困惑如果我们有嵌套类，如何做。

I am trying to display my data in datagridview. I created a class with different property and used its list as the datasource. it worked fine. but I got confused how to do that in case we have nested class.

我的类如下：

class Category
   property UIN as integer
   property Name as string
end class

class item
   property uin as integer
   property name as string
   property mycategory as category
end class

我的数据列表如下：

dim myDataList as list(of Item) = new List(of Item)
myDataList.Add(new Item(1,"item1",new category(1,"cat1")))
myDataList.Add(new Item(2,"item2",new category(1,"cat1")))
myDataList.Add(new Item(3,"item3",new category(1,"cat1")))
myDataList.Add(new Item(4,"item4",new category(2,"cat2")))
myDataList.Add(new Item(5,"item5",new category(2,"cat2")))
myDataList.Add(new Item(6,"item6",new category(2,"cat2")))

现在我绑定了datagridview控件如：

Now I binded the datagridview control like:

DGVMain.AutoGenerateColumns = False
DGVMain.ColumnCount = 3
DGVMain.Columns(0).DataPropertyName = "UIN"
DGVMain.Columns(0).HeaderText = "ID"
DGVMain.Columns(1).DataPropertyName = "Name"
DGVMain.Columns(1).HeaderText = "Name"
DGVMain.Columns(2).DataPropertyName = "" **'here i want my category name**
DGVMain.Columns(2).HeaderText = "category"

DGVMain.datasource = myDataList
DGVMain.refresh()

尝试使用mycategory.name但它没有工作。可以做什么来获得预期的结果？除了这个以外，还有什么更好的想法来完成同样的任务吗？

I have tried using mycategory.name but it didn't worked. What can be done to get expected result? Is there any better idea other than this to accomplish the same task?

编辑我的问题按照注释：

Edited My question as per comment:

我检查了由u给出的链接。这是很好的n非常有用。因为代码是在c＃我试图转换它在vb。一切都很好，但失败在一个大小写敏感，下一个是我有我的嵌套类名称itemcategory和我的属性名称是类别。它唤起了问题。它没有搜索类别，但搜索itemcategory。所以混淆了吧。我的代码如下：

I have checked the link given by u. It was nice n very usefull. Since the code was in c# i tried to convert it in vb. Everything went good but failed at a point of case sensitive and next one is that i had my nested class name itemcategory and my property name was category. there it arouse the problem. it didn't searched for category but it searched for itemcategory. so confused on it. My Code as follows:

Private Sub DGVMain_CellFormatting(ByVal sender As Object, ByVal e As System.Windows.Forms.DataGridViewCellFormattingEventArgs) Handles DGVMain.CellFormatting
    Dim DGVMain As DataGridView = CType(sender, DataGridView)
    e.Value = EvaluateValue(DGVMain.Rows(e.RowIndex).DataBoundItem, DGVMain.Columns(e.ColumnIndex).DataPropertyName)
End Sub

Private Function EvaluateValue(ByRef myObj As Object, ByRef myProp As String) As String
    Dim Ret As String = ""
    Dim Props As System.Reflection.PropertyInfo()
    Dim PropA As System.Reflection.PropertyInfo
    Dim ObjA As Object

    If myProp.Contains(".") Then

        myProp = myProp.Substring(0, myProp.IndexOf("."))
        Props = myObj.GetType().GetProperties()

        For Each PropA In Props

            ObjA = PropA.GetValue(myObj, New Object() {})
            If ObjA.GetType().Name = myProp Then

                Ret = EvaluateValue(ObjA, myProp.Substring(myProp.IndexOf(".") + 1))
                Exit For

            End If

        Next

    Else

        PropA = myObj.GetType().GetProperty(myProp)
        Ret = PropA.GetValue(myObj, New Object() {}).ToString()

    End If

    Return Ret
End Function

推荐答案

Public Class Category
    Dim uni As Integer
    Dim name As String
    Public Sub New(ByVal i As Integer, ByVal n As String)
        Me.UIN = i
        Me.name = n
    End Sub
    Public Sub New()

    End Sub
    Property UIN() As Integer
        Get
            Return uni


        End Get
        Set(ByVal value As Integer)
            uni = value

        End Set
    End Property
    Property Names() As String
        Get
            Return Me.name

        End Get
        Set(ByVal value As String)
            Me.name = value
        End Set
    End Property
    **Public Overrides Function ToString() As String
        Return name.ToString()
    End Function**
End Class

Public Class item
    Dim uni As Integer
    Dim name As String
    Dim category As New Category()

    Property UIN() As Integer
        Get
            Return uni


        End Get
        Set(ByVal value As Integer)
            uni = value

        End Set
    End Property
    Property Names() As String
        Get
            Return Me.name

        End Get
        Set(ByVal value As String)
            Me.name = value
        End Set
    End Property
    Property mycategory() As Category
        Get
            Return Me.category
        End Get
        Set(ByVal value As Category)
            Me.category = value
        End Set
    End Property
    Public Sub New(ByVal i As Integer, ByVal nm As String, ByVal ct As Category)
        Me.UIN = i
        Me.Names = nm
        Me.mycategory = ct
    End Sub
End Class

Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
    Dim myDataList As List(Of item) = New List(Of item)
    myDataList.Add(New item(1, "item1", New Category(1, "cat1")))
    myDataList.Add(New item(2, "item2", New Category(1, "cat1")))
    myDataList.Add(New item(3, "item3", New Category(1, "cat1")))
    myDataList.Add(New item(4, "item4", New Category(2, "cat2")))
    myDataList.Add(New item(5, "item5", New Category(2, "cat2")))
    myDataList.Add(New item(6, "item6", New Category(2, "cat2")))


    DGVMain.AutoGenerateColumns = False
    DGVMain.ColumnCount = 3
    DGVMain.Columns(0).DataPropertyName = "UIN"
    DGVMain.Columns(0).HeaderText = "ID"
    DGVMain.Columns(1).DataPropertyName = "Names"
    DGVMain.Columns(1).HeaderText = "Name"
    **DGVMain.Columns(2).DataPropertyName = "mycategory"**
    DGVMain.Columns(2).HeaderText = "Category"

    DGVMain.datasource = myDataList
    DGVMain.refresh()
End Sub

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