VB重载解析失败

Question

我在编译时遇到这个错误，我不知道为什么~ 任何人都可以解决这个问题。

Overload resolution failed because no accessible 'Add' can be called with these arguments:
    'Public Sub Add(entity As System.ServiceModel.DomainServices.Client.Entity)': Value of type 'LotusUniversityAd.Lecture' cannot be converted to 'System.ServiceModel.DomainServices.Client.Entity'.
    'Public Sub Add(entity As Web.Lecture)': Value of type 'LotusUniversityAd.Lecture' cannot be converted to 'LotusUniversityAd.Web.Lecture'.  C:\Users\Carson\documents\visual studio 2010\Projects\LotusUniversityAd\LotusUniversityAd\Views\Home.xaml.vb

这是背后的代码

Private Sub addMem_Closed(ByVal sender As Object, ByVal e As System.EventArgs)
            Dim mem As RegistrationPage = sender
            If Not mem.NewMem Is Nothing Then
                Dim _OrganizationContext As OrganizationContext = LectureDataSource.DomainContext
                _OrganizationContext.Lectures.Add(mem.NewMem)

                LectureDataSource.SubmitChanges()

End If

这是XAML代码

<navigation:Page 
    xmlns:dataForm="clr-namespace:System.Windows.Controls;assembly=System.Windows.Controls.Data.DataForm.Toolkit"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" 
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" 
    xmlns:d="http://schemas.microsoft.com/expression/blend/2008" xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
    xmlns:navigation="clr-namespace:System.Windows.Controls;assembly=System.Windows.Controls.Navigation"
    xmlns:sdk="http://schemas.microsoft.com/winfx/2006/xaml/presentation/sdk" x:Class="LotusUniversityAd.Home"
    mc:Ignorable="d" d:DesignWidth="640" d:DesignHeight="480"
    Title="Home"
    xmlns:ds="clr-namespace:LotusUniversityAd.Web"
    Style="{StaticResource PageStyle}" xmlns:riaControls="clr-namespace:System.Windows.Controls;assembly=System.Windows.Controls.DomainServices">

<riaControls:DomainDataSource Name="LectureDataSource" QueryName="GetLecture" AutoLoad="True">
            <riaControls:DomainDataSource.DomainContext>
                <ds:OrganizationContext/>
            </riaControls:DomainDataSource.DomainContext>
        </riaControls:DomainDataSource>
    </Grid>
</navigation:Page>

Answer 1

mem.NewMem 的类型为 LotusUniversityAd.Lecture，您可能有一个采用 LotusUniversityAd.Web.Lecture 类型的 DomainContext Insert 方法（如果没有，您将需要一个）。

请注意命名空间的差异。如果您解决了这个问题，您的错误可能会得到纠正。如果您已在 silverlight 项目中定义了讲座类，请确保它位于 Web 命名空间内并定义为分部类。