'**********************************************
'说明:将DataTable转化为泛型集合
'命名空间：DAL
'机器名称：晓
'创建日期：2015/2/23 11:13:28
'作者：郑浩
'版本号：V1.00
'**********************************************

Imports System.Collections.Generic  '增加泛型的命名空间  
Imports System.Reflection '引入反射：为了使用PropertyInfo 
Public Class  ConvertGenericsHelper
    '将datatable转化为泛型集合  
    Public Shared Function convertToList(Of T As {New})(ByVal dt As DataTable) As IList(Of T)
        '注意：convertToList(Of T As {New}) 这里的new是用来约束T的，必须有，不然new T的时候会出现错误  

        Dim myList As New List(Of T)   '定义最终返回的集合  

        Dim myTpye As Type = GetType(T) '得到实体类的类型名  
        Dim dr As DataRow   '定义行集  

        Dim tempName As String = String.Empty   '定义一个临时变量  

        '遍历DataTable的所有数据行  
        For Each dr In dt.Rows

            Dim myT As New T    '定义一个实体类的对象  
            Dim propertys() As PropertyInfo = myT.GetType().GetProperties()  '定义属性集合  
            Dim Pr As PropertyInfo

            '遍历该对象的所有属性  
            For Each Pr In propertys
                tempName = Pr.Name '将属性名称赋值给临时变量  

                '检查DataTable是否包含此列（列名==对象的属性名）   
                If (dt.Columns.Contains(tempName)) Then     '将此属性与datatable里的列明比较，查看datatable是否包含此属性  
                    '判断此属性是否有Setter  
                    If (Pr.CanWrite = False) Then   '判断此属性是否可写，如果不可写，跳出本次循环  
                        Continue For
                    End If
                    Dim value As Object = dr(tempName)  '定义一个对象型的变量来保存列的值  
                    If (value.ToString <> DBNull.Value.ToString()) Then '如果非空，则赋给对象的属性  
                        Pr.SetValue(myT,value,Nothing)    '在运行期间，通过反射，动态的访问一个对象的属性  
                    End If
                End If
            Next
            myList.Add(myT)   '添加到集合  
        Next
        Return myList   '返回实体集合  
    End Function
End Class

D层代码

'**********************************************
'说明:利用泛型集合来查看学生余额
'命名空间：DAL
'机器名称：晓
'创建日期：2015/2/23 11:27:21
'作者：郑浩
'版本号：V1.00
'**********************************************
Imports IDAL
Imports System.Data.sqlClient
Public Class sqlserverCheckBalanceDAL : Implements ICheckBalance


    Public Function ICheckBalance(studentinfo As Entity.EN_StudentInfo) As List(Of Entity.EN_StudentInfo) Implements ICheckBalance.ICheckBalance
        Dim sql As String
        sql = "select * from ZH_StudentInfo where CardNo = @CardNo"
        Dim paras As sqlParameter() = {New sqlParameter("CardNo",studentinfo.CardNo)}
        Dim dt As New DataTable
        '保存转换后的泛型集合  
        Dim myList As New List(Of Entity.EN_StudentInfo)
        dt = sqlHelper.sqlHelper.ExecSelect(sql,CommandType.Text,paras)
        '先判断dt是否为空  
        If dt.Rows.Count > 0 Then
            '将dt转换为泛型集合  
            myList = ConvertGenericsHelper.convertToList(Of Entity.EN_StudentInfo)(dt)
            Return myList
        Else
            Return Nothing
        End If
    End Function
End Class

       ’直接给文本框赋值

        Dim studentinfo As New Entity.EN_StudentInfo
        studentinfo.CardNo = Trim(txtCardNo.Text)
        Dim dt As New List(Of Entity.EN_StudentInfo)
        Dim checkbalance As New Facade.FacadeCheckBalance
        dt = checkbalance.CheckBalance(studentinfo)

        txtClass.Text = dt(0).Classes  '0表示泛型集合中的第一个实体
        txtStudentNo.Text = dt(0).StudentNo
        txtName.Text = dt(0).StudentName
        txtSex.Text = dt(0).Sex
        txtStatus.Text = dt(0).Status
        txtGrade.Text = dt(0).Grade
        txtBalance.Text = dt(0).Cash
        txtExplain.Text = dt(0).Explain
    End Sub

  ’和DataGridView控件交互

    Private Sub Button2_Click(sender As Object,e As EventArgs) Handles Button2.Click
        Dim studentinfo As New Entity.EN_StudentInfo
        studentinfo.CardNo = Trim(txtCardNo.Text)
        Dim dt As New List(Of Entity.EN_StudentInfo)
        Dim checkbalance As New Facade.FacadeCheckBalance
        dt = checkbalance.CheckBalance(studentinfo)

        dgvRecord.DataSource = dt
        dgvRecord.AutoGenerateColumns = True
        dgvRecord.Columns(1).HeaderText = "卡号"
    End Sub