WPF DataGrid: How to Determine the Current Row Index?

问题

I am trying to implement a very simple spreadsheet functionality based on a DataGrid.

The user clicks on a cell
The user types a value and presses return
The current row is scanned and any cell formula that depends on the clicked cell is updated.

This seems to be the best event handler for my requirements:

private void my_dataGrid_CurrentCellChanged(object sender, EventArgs e)

Question: How do I detect the row index of the current row?

回答1:

Try this (assuming the name of your grid is "my_dataGrid"):

var currentRowIndex = my_dataGrid.Items.IndexOf(my_dataGrid.CurrentItem);

Normally, you'd be able to use my_dataGrid.SelectedIndex, but it seems that with the CurrentCellChanged event, the value of SelectedIndex always displays the previously selected index. This particular event seems to fire before the value of SelectedIndex actually changes.

回答2:

Hi you can do something like this to do your spreadsheed

 //not recomended  as it always  return the previous index of the selected row 
 void dg1_CurrentCellChanged(object sender, EventArgs e)
    {

       int rowIndex = dg1.SelectedIndex;   
     }

but if you want a more elaborated example this is how you can do it

namespace WpfApplication2
{
/// <summary>
/// Interaction logic for MainWindow.xaml
/// </summary>
public partial class MainWindow : Window
{
    ObservableCollection<Tuple<string,string>> observableCollection = new ObservableCollection<Tuple<string,string>>();  
    public MainWindow()
    {
        InitializeComponent();            
        for (int i = 0; i < 100; i++)
        {
            observableCollection.Add( Tuple.Create("item " + i.ToString(),"=sum (c5+c4)"));
        }

        dg1.ItemsSource = observableCollection; 

        dg1.CurrentCellChanged += dg1_CurrentCellChanged;

    }

    void dg1_CurrentCellChanged(object sender, EventArgs e)
    {
        //int rowIndex = dg1.SelectedIndex;   
        Tuple<string, string> tuple = dg1.CurrentItem as Tuple<string, string>; 
        //here as you have your datacontext you can loop through and calculate what you want 

    }
}
}

Hope this help

回答3:

The solution from Grant will work until you have no reference-duplicates in the ItemsSource, otherwise you will get index of the object's first occurrence.

The solution from BRAHIM Kamel will work until you have a selection, otherwise(if you click twice and deselect a cell/row) you will not have a SelectedIndex.

With YourDataGrid.ItemContainerGenerator.ContainerFromItem( _dataItemFromCurentCell ) as DataGridRow you will get by duplicates always the last occurrence of data item.

I would handle DataGrid.PreviewMouseLeftButtonDown event and search in handler the visual tree up to a DatagridRow, which has DatagridRow.GetIndex() method. So you will get always the right row index.

<DataGrid ... PreviewMouseLeftButtonDown="Previe_Mouse_LBtnDown" >
    ...
</DataGrid>

private void Previe_Mouse_LBtnDown(object sender, MouseButtonEventArgs e)
{
    DataGridRow dgr = null;
    var visParent = VisualTreeHelper.GetParent(e.OriginalSource as FrameworkElement);
    while (dgr == null && visParent != null)
    {
        dgr = visParent as DataGridRow;
        visParent = VisualTreeHelper.GetParent(visParent);
    }
    if (dgr == null) { return; }

    var rowIdx=dgr.GetIndex();
}

回答4:

GRD.Items.Count;
DataGridRow row = (DataGridRow) GRD.ItemContainerGenerator.ContainerFromIndex(i);     
DataGridCell TXTGROUPID = GRD.Columns[2].GetCellContent(row).Parent as DataGridCell;               
string str = ((TextBlock) TXTGROUPID.Content).Text;
MessageBox.Show(str);

来源：https://stackoverflow.com/questions/20169765/wpf-datagrid-how-to-determine-the-current-row-index

标签

wpf

datagrid

datagridcell