问模型包含集合的ASP.NET Web Forms 4.5模型绑定

EN

public static string CreateIndexModelName(string parentName, string index)
{
    if (parentName.Length != 0)
    {
        return (parentName + "[" + index + "]");
    }
    return ("[" + index + "]");
}

<div id="selectOptions">
    <asp:FormView runat="server" ID="fvProductSelection" DefaultMode="Edit"
        ItemType="Models.ProductChoice"
        SelectMethod="GetProduct"
        UpdateMethod="UpdateProduct" >
        <EditItemTemplate>
            <asp:linkbutton id="UpdateButton" text="Update" commandname="Update" runat="server"/>
            <asp:HiddenField runat="server" ID="ProductId" Value="<%# BindItem.ProductId %>" />
            <asp:TextBox Text ="<%# BindItem.Quantity %>" ID="Quantity" runat="server" />

            <% for (int i = 0; i < BindItem.Extras.Count; i++)
            { %>
                    <asp:HiddenField Value="<%# BindItem.Extras[i].ExtraProductId %>" ID="ExtraProductId" runat="server"  />
                    <asp:Label Text="<%# BindItem.Extras[i].ExtraName %>" ID="Name" runat="server" />
                    <asp:TextBox Text="<%# BindItem.Extras[i].ExtraQuantity %>" ID="Quantity"  runat="server" />
            <% } %> 
        </EditItemTemplate>
    </asp:FormView>
</div>

public partial class Student
{
    [System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Usage", "CA2214:DoNotCallOverridableMethodsInConstructors")]
    public Student()
    {
        this.Enrollments = new List<Enrollment>();
    }

    public int Id { get; set; }
    public string LastName { get; set; }
    public string FirstName { get; set; }
    public Nullable<int> YearId { get; set; }

    [System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Usage", "CA2227:CollectionPropertiesShouldBeReadOnly")]
    public virtual List<Enrollment> Enrollments { get; set; }
    public virtual AcademicYear AcademicYear { get; set; }
}


public partial class Enrollment
{
    public int Id { get; set; }
    public Nullable<decimal> Grade { get; set; }
    public Nullable<int> CourseId { get; set; }
    public Nullable<int> StudentId { get; set; }

    public virtual Course Course { get; set; }
    public virtual Student Student { get; set; }
}

<asp:FormView runat="server" ID="addStudentForm"
    DataKeyNames="Id"
    ItemType="WebApplication3.Student" 
    UpdateMethod="addStudentForm_UpdateItem" DefaultMode="Edit"
    RenderOuterTable="false" OnItemUpdated="addStudentForm_ItemUpdated"
    SelectMethod="addStudentForm_GetItem">
    <EditItemTemplate>            
        <fieldset>
        
            <asp:HiddenField ID="Id" Value="<%# BindItem.Id %>" runat="server" />
            <asp:Panel ID="Panel1" runat="server">

                <asp:Label ID="Label1" runat="server" Text="FirstName: "></asp:Label>
                <asp:TextBox ID="FirstName" runat="server" Width="70%" Text="<%# BindItem.FirstName %>" ></asp:TextBox>

            </asp:Panel>

            <asp:Panel ID="Panel2" runat="server">

                <asp:Label ID="Label2" runat="server" Text="LastName: "></asp:Label>
                <asp:TextBox ID="LastName" runat="server" Width="70%" Text="<%# BindItem.LastName %>" ></asp:TextBox>

            </asp:Panel>

            <asp:Panel ID="Panel4" runat="server"  >
                <% for (int i = 0; i < enrollments.Count; i++)
                    { %>

                    // ```name``` is constructed like in MVC
                    <input hidden id="test" type="text" name="Enrollments[<%= i %>].Id" value='<%= enrollments[i].Id %>'/>
                    <input id="test1" type="text" name="Enrollments[<%= i %>].Grade" value='<%= enrollments[i].Grade %>' />
                <%  } %>

            </asp:Panel>
                            
            <asp:Button runat="server" Text="Edit" CommandName="Update" />
            <asp:Button runat="server" Text="Cancel" CausesValidation="false" OnClick="Cancel_Click" />
        </fieldset>
    </EditItemTemplate>
</asp:FormView>

public List<Enrollment> enrollments = new List<Enrollment>(); // Contain the data after ```SelectMethod``` from db, is for ```for``` loop in Controls page

protected void Page_Load(object sender, EventArgs e)
{
}

public void addStudentForm_UpdateItem(Student student) // At this line, the ```student``` will be bound with data from ASP SerVer Control only
{

    // Add these 3 lines of code to use MVC approach.
    // THis kind of binding uses prefix like [] or ., which ASP server controls are not accepted
    NameValueCollection nameValues = Request.Form;

    IValueProvider provider = new NameValueCollectionValueProvider(nameValues, System.Globalization.CultureInfo.CurrentUICulture);

    TryUpdateModel(student, provider); // After this, the ```student``` will be bound with Form Values that have their ```key``` (```name``` attribute) being constructed like MVC approach (see above Control code).

    // Database update go here
    
}

- It only works with HTML element (and without `runat=server`), because of the requirement for `name` attribute (of `<input>` or `<select>` for example). You get what I mean? The Webform Server Controls have its own design for `name` properties, which is designed to fit it own model binding, which not being accepted in MVC. That's why you cannot set `name` properties, and if you try to change it with Jquery/JavaScript/Code-Behind, the model binding for the Webform Server Controls will not work.
- This approach only use "MVC style" `name` to bind. So it will not bind the ASP Server Control style `name` (like `$Maincontent$...` thing).
- The binding for Webform Server Controls approach and MVC approach cant be merged in one. I had to do one after one like in my example.