【WPF异常】在使用 ItemsSource 之前，项集合必须为空

 <DataGrid x:Name="dataGrid" HorizontalAlignment="Left" Margin="10,10,0,0" VerticalAlignment="Top" Width="" Height="" AutoGenerateColumns="False" GridLinesVisibility="None" CanUserDeleteRows="False"
                     CanUserAddRows="False" ItemsSource="{Binding ListStudent}">
             <DataGridTextColumn Header="编号" Width="" Binding="{Binding Student.studentid}"/>
             <DataGridTextColumn Header="姓名" Width="" Binding="{Binding Student.name}"/>
             <DataGridTextColumn Header="年龄" Width="" Binding="{Binding Student.age}"/>
             <DataGridTextColumn Header="性别" Width="" Binding="{Binding Student.sex}"/>
             <DataGridTextColumn Header="特点" Width="" Binding="{Binding Student.remark}"/>
             <DataGridTemplateColumn Header="选中" SortMemberPath="IsSelected" Width="">
                 <DataGridTemplateColumn.CellTemplate>
                     <DataTemplate>
                         <CheckBox IsChecked="{Binding Path=IsSelected,UpdateSourceTrigger=PropertyChanged}" VerticalAlignment="Center" HorizontalAlignment="Center" Command="{Binding Path=DataContext.SelectStudentItemCommand,RelativeSource={RelativeSource Mode=FindAncestor,AncestorType={x:Type DataGrid}}}"
                     />
                     </DataTemplate>
                 </DataGridTemplateColumn.CellTemplate>
             </DataGridTemplateColumn>
         </DataGrid>

报错“在使用 ItemsSource 之前，项集合必须为空”

观察一下便可发现设计器里没有正确显示各列，是因为少了DataGrid.Columns节点

 <DataGrid x:Name="dataGrid" HorizontalAlignment="Left" Margin="10,10,0,0" VerticalAlignment="Top" Width="" Height="" AutoGenerateColumns="False" GridLinesVisibility="None" CanUserDeleteRows="False"
                     CanUserAddRows="False" ItemsSource="{Binding ListStudent}">
             <DataGrid.Columns>
             <DataGridTextColumn Header="编号" Width="" Binding="{Binding Student.studentid}"/>
             <DataGridTextColumn Header="姓名" Width="" Binding="{Binding Student.name}"/>
             <DataGridTextColumn Header="年龄" Width="" Binding="{Binding Student.age}"/>
             <DataGridTextColumn Header="性别" Width="" Binding="{Binding Student.sex}"/>
             <DataGridTextColumn Header="特点" Width="" Binding="{Binding Student.remark}"/>
             <DataGridTemplateColumn Header="选中" SortMemberPath="IsSelected" Width="">
                 <DataGridTemplateColumn.CellTemplate>
                     <DataTemplate>
                         <CheckBox IsChecked="{Binding Path=IsSelected,UpdateSourceTrigger=PropertyChanged}" VerticalAlignment="Center" HorizontalAlignment="Center" Command="{Binding Path=DataContext.SelectStudentItemCommand,RelativeSource={RelativeSource Mode=FindAncestor,AncestorType={x:Type DataGrid}}}"
                     />
                     </DataTemplate>
                 </DataGridTemplateColumn.CellTemplate>
             </DataGridTemplateColumn>
             </DataGrid.Columns>
         </DataGrid>

改为以上即可