1、DataGrid命名为planDataGrid

<DataGrid ItemsSource="{Binding PlanList}" SelectedItem="{Binding SelectedItem}" x:Name="planDataGrid" AutoGenerateColumns="False" CanUserAddRows="False"
          GridLinesVisibility="All" FontSize="12" ColumnHeaderHeight="42" RowHeaderWidth="0" EnableRowVirtualization="False" VirtualizingPanel.IsVirtualizing="False">

</DataGrid>

2、  SetSelectedItemFirstRow(page.planDataGrid);调用方法，获取到前端界面的DataGrid，传给后端使用。

 void SetSelectedItemFirstRow(object dataGrid){//若目标datagrid为空，抛出异常if (dataGrid == null){throw new ArgumentNullException("目标无" + dataGrid + "无法转换为DataGrid");}//获取目标DataGrid，为空则抛出异常System.Windows.Controls.DataGrid dg = dataGrid as System.Windows.Controls.DataGrid;if (dg == null){throw new ArgumentNullException("目标无" + dataGrid + "无法转换为DataGrid");}//数据源为空则返回if (dg.Items == null || dg.Items.Count < 1){return;}dg.SelectedItem = dg.Items[0];dg.CurrentColumn = dg.Columns[0];dg.ScrollIntoView(dg.SelectedItem, dg.CurrentColumn);//获取焦点，滚动为目标行dg.Focus();dg.SelectedItem = selectedItem;//设置选中行dg.CurrentColumn = dg.Columns[0];dg.ScrollIntoView(dg.SelectedItem, dg.CurrentColumn);var item = dg.SelectedItem as PlanDataModel;ObservableCollection<CoilListModel> clm = new ObservableCollection<CoilListModel>();DBHandle.GetCoilsByJobId(item, ref clm);CoilList = clm;page.coilDataGrid.ItemsSource = CoilList;}