选定的数据源上未找到名为“productname”的字段或属性 请教高手

Question

前台代码
...
<asp:GridView ID="gvdSearchMessageLog" runat="server" 
                     AutoGenerateColumns="False" CellPadding="4" ForeColor="#333333" 
                     GridLines="None" Width="100%">
                     <RowStyle BackColor="#EFF3FB" />
                     <Columns>
                         <asp:BoundField DataField="id" HeaderText="id" Visible="False" />
                         <asp:BoundField DataField="productname" HeaderText="商品名称" />
                         <asp:BoundField DataField="contents" HeaderText="留言内容" />
                         <asp:BoundField DataField="usersname" HeaderText="留言人" />
                         <asp:BoundField DataField="mtime" HeaderText="留言时间" />
                         <asp:TemplateField HeaderText="操作">
                             <EditItemTemplate>
                                 <asp:TextBox ID="TextBox1" runat="server"></asp:TextBox>
                             </EditItemTemplate>
                             <ItemTemplate>
                                 <asp:Label ID="Label1" runat="server"></asp:Label>
                             </ItemTemplate>
                         </asp:TemplateField>
                     </Columns>
                     <FooterStyle BackColor="#507CD1" Font-Bold="True" ForeColor="White" />
                     <PagerStyle BackColor="#2461BF" ForeColor="White" HorizontalAlign="Center" />
                     <SelectedRowStyle BackColor="#D1DDF1" Font-Bold="True" ForeColor="#333333" />
                     <HeaderStyle BackColor="#507CD1" Font-Bold="True" ForeColor="White" />
                     <EditRowStyle BackColor="#2461BF" />
                     <AlternatingRowStyle BackColor="White" />
</asp:GridView>后台代码     protected void gvdSearchMessageLog_Bind()
    {
        gvdSearchMessageLog.DataSource = GetEvaluateInfo.GetMessage();
        gvdSearchMessageLog.DataBind();
    }//得到数据.    private const string Sql_Evaluate_Select = "select a.id,b.productname,contents,usersname,mtime from evaluate a,product b,users c where a.productid=b.id and a.userid=c.id";    public List<Model.Back_Evaluate> GetMessage()
   {
     List<Model.Back_Evaluate> evaluateinfo = new List<Model.Back_Evaluate>();
     using (SqlDataReader rdr = SQLHelper.ExecuteReader(SQLHelper.ConnectionStringLocalTransaction, CommandType.Text, Sql_Evaluate_Select, null))
            {
                while (rdr.Read())
                {
                    Model.Back_Evaluate GetEvalInfo = new Model.Back_Evaluate(rdr.GetInt32(0),rdr.GetString(1),rdr.GetString(2),rdr.GetString(3),rdr.GetDateTime(4));
                    evaluateinfo.Add(GetEvalInfo);
                }
            }
            return evaluateinfo;
        }我是新手,取值是成功的..就是绑定GRIDVIEW时,,就是出错...字段名我都是复制的...请高手看看

Answer 1

那就看看你Back_Evaluate实体类里面的属性是否写正确了。

Answer 2

实体类
public class Back_Evaluate
    {
        private int id;        public int Id
        {
            get { return id; }
            set { id = value; }
        }        private string productname;        public string Productname
        {
            get { return productname; }
            set { productname = value; }
        }        private string contents;        public string Contents
        {
            get { return contents; }
            set { contents = value; }
        }        private string usersname;        public string Usersname
        {
            get { return usersname; }
            set { usersname = value; }
        }        private DateTime mtime;        public DateTime Mtime
        {
            get { return mtime; }
            set { mtime = value; }
        }        public Back_Evaluate() { }        public Back_Evaluate(int id, string productname, string contents, string usersname, DateTime mtime)
        {
            this.id = id;
            this.productname = productname;
            this.contents = contents;
            this.usersname = usersname;
            this.mtime = mtime;
        }
    }
数据表
CREATE TABLE [dbo].[evaluate](
[id] [int] IDENTITY(1,1) NOT NULL,
[productid] [int] NULL,
[score] [int] NULL,
[contents] [varchar](200) NULL,
[mtime] [datetime] NULL,
[userid] [int] NULL,
[Reply] [varchar](200) NULL,CREATE TABLE [dbo].[users](
[id] [int] IDENTITY(1,1) NOT NULL,
[usersname] [varchar](30) NULL,
[password] [varchar](20) NULL,
[keeppwd] [varchar](30) NULL,
[regiter] [datetime] NULL,
[lastlogin] [datetime] NULL,
[email] [varchar](30) NULL,
[stateuing] [int] NULL,
[points] [int] NULL,
[VIP] [int] NULL,
[roles] [varchar](10) NULL,
[question] [varchar](30) NULL,
[result] [varchar](30) NULL,
[uptime] [datetime] NULL,
[outtime] [datetime] NULL,
[addreess] [varchar](50) NULL,
[QQ] [varchar](30) NULL,
[MSN] [varchar](30) NULL,
[Mobile] [varchar](30) NULL,
[TEl] [varchar](30) NULL,CREATE TABLE [dbo].[product](
[id] [int] NOT NULL,
[pid] [int] NULL,
[productname] [varchar](30) NULL,
[entryword] [varchar](2) NULL,
[productnumber] [varchar](50) NULL,
[images] [varchar](100) NULL,
[price] [decimal](8, 2) NULL,
[myprice] [decimal](8, 2) NULL,
[VIPprice] [decimal](8, 2) NULL,
[groupprice] [decimal](8, 2) NULL,
[groups] [int] NULL,
[least] [int] NULL,
[look] [int] NULL,
[ettime] [varchar](50) NULL,
[weight] [varchar](20) NULL,
[stockpile] [int] NULL,
[re] [varchar](200) NULL,
[exchange] [int] NULL,
[point] [int] NULL,
[stateuing] [int] NULL,
[new] [int] NULL,
[score] [int] NULL,
[level] [int] NULL,

Answer 3

你到数据库里单独执行一下
select a.id,b.productname,contents,usersname,mtime from evaluate a,product b,users c where a.productid=b.id and a.userid=c.id
看看是否有数据。