Welcome to OGeek Q&A Community for programmer and developer-Open, Learning and Share
Welcome To Ask or Share your Answers For Others

Categories

0 votes
945 views
in Technique[技术] by (71.8m points)

asp.net mvc - MVC LINQ to SQL Table Join Record Display

Im having problems displaying records to my view when passing viewdata to a user control. This is only apparent for linq to sql objects where I am using table joins.

The exception I receive is "Unable to cast object of type '<>f__AnonymousType410[System.String,System.Int32,System.Nullable1[System.DateTime],System.String,System.String,System.String,System.String,System.String,System.Nullable1[System.Single],System.Nullable1[System.Double]]' to type App.Models.table1."

I have searched for a fix to this issue but not too familiar on whats wrong here for me to search for the right subject. This should be working in theory and this works for single table retrieving but when I added a join in their I ran into problems. I am currently using a foreach statement to query through my data via single table declaration. Any help would be greatly appreciated. Thanks in advance.

My current setup is:

CViewDataUC.cs(my class to hold viewdata and data connections specifically for user controls)

public void Info(ViewDataDictionary viewData, int id)
    {
        var dataContext = new testDataContext();

        var info = from table1 in dataContext.table1
                   join table2 in dataContext.table2 on table1.type_id equals table2.type_id
                   join table3 in dataContext.table3 on table1.id equals table3.id
                   join table4 in dataContext.table4 on table1.id equals table4.id
                   where table1.id == id
                   select new
                   {
                       table1.column1,
                       table1.column2,
                       table1.column3,
                       table1.column4,
                       table1.column5,
                       table1.column6,
                       table1.column7,
                       table2.column1,
                       table3.column1,
                       table4.column1
                   };         

        viewData["vd_Info"] = info;

    }

HomeController.cs(Controller)

public ActionResult Information(int id)
        {
            ViewData["Title"] = "Information";


            CViewDataUC o_info = new CViewDataUC();

            o_info.Info(this.ViewData, id);


            return View();
        }

Information.aspx(View)

<%@ Page Title="" Language="C#" MasterPageFile="~/Views/Shared/Site.Master" AutoEventWireup="true"
    CodeBehind="Info.aspx.cs" Inherits="App.Views.Info" %>

<asp:Content ID="Content1" ContentPlaceHolderID="MainContent" runat="server">
    <%Html.RenderPartial("~/Views/UserControls/Info.ascx", ViewData["vd_Info"]);%>
</asp:Content>

Info.ascx(User Control)

<%foreach (table1 m in (IEnumerable)ViewData.Model)
  { %>
<div class="left">
    <br />
    <br />
    <p id="medium">
        Column 1
        <br />
        <%= Html.TextBox("column1", m.column1, new {@class = "textBox", @readonly = "readonly" })%>
        Column 1
        <br />
        <%= Html.TextBox("column2", m.column2, new {@class = "textBox", @readonly = "readonly" })%>
        <br />
        Column 1
        <br />
        <%= Html.TextBox("column3", m.column3, new {@class = "textBox", @readonly = "readonly" })%>
                </p>
</div>
<%}%>
See Question&Answers more detail:os

与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
Welcome To Ask or Share your Answers For Others

1 Reply

0 votes
by (71.8m points)
foreach (table1 m in (IEnumerable)ViewData.Model)

m is not of type table1. It is an anonymous type (select new { ... } in CViewDataUC.cs).

You should create a class that represents the type of the model objects you are passing from controller to view.


与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
OGeek|极客中国-欢迎来到极客的世界,一个免费开放的程序员编程交流平台!开放,进步,分享!让技术改变生活,让极客改变未来! Welcome to OGeek Q&A Community for programmer and developer-Open, Learning and Share
Click Here to Ask a Question

...