Deleting Row from Grid or DataTable Associated with Grid

[Jorge Gonzalez]

Hello,

    When trying to delete specific rows from the WPF grid I get this error when I execute this command:

grid_name.Items.RemoveAt(<position of row to delete>);

The error is: Operation is not valid while ItemsSource is in use. Access and modify elements with ItemsControl.ItemsSource instead.

When I try deleting row 2 or greater from the datatable I get an error message saying that I've tried deleting an entry in the datatable that does not exist. Essentially an out of bounds error. Strangely enough I can delete the first row.

If I break the association between the grid and the datatable by doing this I can delete whatever row I want.

grid_name.ItemsSource = null;

datatable_name.Rows.RemoveAt(<position of row to delete>);

grid_name.ItemsSource = dataset_name.Tables[0].DefaultView; // I only have 1 datatable in the dataset.

Is this the correct way to delete stuff from the grid?

[Rossen Hristov]

Hi Jorge Gonzalez,

You should delete rows from the DataTable itself like this:

using System.Windows;
using Telerik.Windows.Controls;
using Telerik.Windows.Data;
using System.Data;
using System;
using System.Text;

namespace TicketID_265559_DeleteARowFromDataTable
{
    /// <summary>
    /// Interaction logic for Window1.xaml
    /// </summary>
    public partial class Window1 : Window
    {
        DataTable dataTable;

        public Window1()
        {
            InitializeComponent();

            this.dataTable = new DataTable();
            dataTable.Columns.Add("StringColumn", typeof(string));
            dataTable.Columns.Add("DoubleColumn", typeof(double));
            dataTable.Columns.Add("DateTimeColumn", typeof(DateTime));

            Random random = new Random();
            for (int i = 0; i < 100; i++)
            {
                StringBuilder stringValue = new StringBuilder();
                for (int j = 0; j < 20; j++)
                {
                    stringValue.Append((char)random.Next(32, 126));
                }

                dataTable.Rows.Add(
                    stringValue.ToString()
                    , (random.NextDouble() * 100000) * (Math.Pow(-1, random.Next(0, 10)))
                    , DateTime.Now.AddDays(random.Next(-365, +365)));
            }

            this.grid.ItemsSource = dataTable.DefaultView;
        }

        private void OnDeleteSelectedRow(object sender, RoutedEventArgs e)
        {
            var index = this.grid.Items.IndexOf(this.grid.SelectedItem);

            if (index > -1)
            {
                this.dataTable.Rows.RemoveAt(index);
            }
        }
    }
}

I have attached a sample project that demonstrates this. I am not sure why your DataTable has only one row. You can try to modify my sample project to reproduce the behavior that you are experiencing and send it back. We will take a look.

Regards,
Ross
the Telerik team

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[Jorge Gonzalez]

If the grid is not associated with the datatable default view use this:

grid_name.ItemsSource = null;

datatable_name.Rows.RemoveAt(<position of row to delete>);

grid_name.ItemsSource = dataset_name.Tables[0]; // No DefaultView appended