Question

我有一个简单的datatgrid，当我按以下方式定义它时可以工作：

    <DataGrid             
        ItemsSource="{Binding EmployeeCollectionViewSource.View}"        
        Style="{DynamicResource FTC_DataGridStyle}" AutoGenerateColumns="True" />

如果我删除AutoGenerateColumns =“True”并尝试按如下方式定义我的列，则会收到错误消息：

     <DataGrid             
        ItemsSource="{Binding EmployeeCollectionViewSource.View}"        
        Style="{DynamicResource FTC_DataGridStyle}" >
        <DataGrid.Columns>
            <DataGridTextColumn Binding="{Binding idCertification}" Header="ID" Width="50" IsReadOnly="True" CellStyle="{DynamicResource IDCellStyle}"/>
            <DataGridTextColumn Binding="{Binding chrTitle}" Header="TITLE" Width="130" CellStyle="{DynamicResource TextCellStyle}"/>
            <DataGridTextColumn Binding="{Binding chrDetail}" Header="DETAIL" Width="300" CellStyle="{DynamicResource TextCellStyle}"/>
            <DataGridTextColumn Binding="{Binding chrProvider}" Header="PROVIDER" Width="130" CellStyle="{DynamicResource TextCellStyle}"/>
        </DataGrid.Columns> />
    </DataGrid>

我得到的错误是：

{“'为类型集合添加值 'System.Windows.Controls.ItemCollection'引发了一个异常。线数字'31'和行位置'32'。“} {”操作无效时 ItemsSource正在使用中。使用访问和修改元素 ItemsControl.ItemsSource代替。“}

我使用MVVM模式，EmployeeCollectionViewSource的绑定是一个collectionviewsource，它是从实体framemowrk生成的ObservableCollection中填充的。

我尝试删除列并仔细检查绑定名称，我无法弄清楚此错误的来源。输出窗口中没有显示错误。

问题您能否帮我解决此错误，以便我可以手动定义我的列？

其他详细信息 以下是我的viewmodel类：

    Public Class EmployeeCertificationViewModel
        Inherits ViewModelBase

#Region "DECLARATIONS"

        Public Const CertificationCollectionPropertyName As String = "EmployeeCertifications"
        Public Const EmployeeCollectionViewSourcePropertyName As String = "EmployeeCollectionViewSource"

        ''this is a holder for the employee data service
        Private _EmployeeAccess As IEmployeeDataService

        Private _EmployeeCertifications As New ObservableCollection(Of certification)
        Private _EmployeeCollectionViewSource As New CollectionViewSource

        ''tracks if employee validation is coming from navigation or listview selecteditemchanged
        Private FlagNavigating As Boolean = False
        Private _NavigationService As INavigationService

        Private _ModelService As IModelService
        Private Context As FTC_Context

#End Region

#Region "PROPERTIES"

        Public Property EmployeeCertifications As ObservableCollection(Of certification)
            Get
                Return Me._EmployeeCertifications
            End Get
            Set(ByVal value As ObservableCollection(Of certification))
                Me._EmployeeCertifications = value
                RaisePropertyChanged(CertificationCollectionPropertyName)
            End Set
        End Property

        Public Property EmployeeCollectionViewSource As CollectionViewSource
            Get
                Return Me._EmployeeCollectionViewSource
            End Get
            Set(value As CollectionViewSource)
                If _EmployeeCollectionViewSource Is value Then
                    Return
                End If
                _EmployeeCollectionViewSource = value
                RaisePropertyChanged(EmployeeCollectionViewSourcePropertyName)
            End Set
        End Property


#End Region

#Region "COMMANDS"

#End Region

#Region "METHODS"

#End Region

#Region "CONSTRUCTOR"
        Public Sub New(NavService As INavigationService, EmployeeService As IEmployeeDataService, ModelService As IModelService)

            _ModelService = ModelService
            Context = _ModelService.NewContext

            _NavigationService = NavService
            _EmployeeAccess = EmployeeService

            EmployeeCertifications = EmployeeService.Get_Certification(Context)
            EmployeeCollectionViewSource.Source = EmployeeCertifications

        End Sub

#End Region

    End Class

Answer 1

默认情况下，

DataGrid.AutoGenerateColumns Property true 。如果要定义自己的列，则必须明确将其设置为false。否则，您将同时拥有两种列类型（自动生成和自定义）。

<DataGrid ItemsSource="{Binding}" AutoGenerateColumns="False">
    <DataGrid.Columns>
        ...
    </DataGrid.Columns>
</DataGrid>

但您的真正问题似乎是代码中/>之后的其他 </DataGrid.Columns> 。删除它，异常应该消失。

不自动生成列时WPF Datagrid绑定错误

1 个答案: