How to: Validate Data Rows and Indicate Errors

  • 5 minutes to read

This example shows how to check if a user enters valid data into a row. Handle the GridViewBase.ValidateRow and GridViewBase.InvalidRowException events to validate the focused row’s data. If the data is invalid, do not allow the user to move focus to another row until the invalid values are corrected.

The Task class implements the IDXDataErrorInfo interface and allows you to get error descriptions for the entire row and for individual cells (data source fields). Error icons appear in cells that contain invalid values. Hover the mouse pointer over an error icon to display a tooltip with an error description.

View Example

<Window x:Class="DXGrid_ValidateRow.Window1" 
    Title="Window1" Height="300" Width="500">
        <dxg:GridControl x:Name="grid">
                <dxg:GridColumn FieldName="TaskName" />
                <dxg:GridColumn FieldName="StartDate" />
                <dxg:GridColumn FieldName="EndDate" />
                <dxg:TableView AutoWidth="True" 
                               InvalidRowException="TableView_InvalidRowException" />
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Navigation;
using System.Windows.Shapes;
using System.Data;
using DevExpress.Xpf.Grid;
using DevExpress.XtraEditors.DXErrorProvider;

namespace DXGrid_ValidateRow {
    public partial class Window1 : Window {
        public Window1() {
            grid.ItemsSource = TaskList.GetData();

        private void TableView_ValidateRow(object sender, GridRowValidationEventArgs e) {
            DateTime startDate = ((Task)e.Row).StartDate;
            DateTime endDate = ((Task)e.Row).EndDate;
            e.IsValid = startDate < endDate;

        private void TableView_InvalidRowException(object sender, InvalidRowExceptionEventArgs e) {
            e.ExceptionMode = ExceptionMode.NoAction;

    public class TaskList {
        public static List<Task> GetData() {
            List<Task> data = new List<Task>();
            data.Add(new Task() { TaskName = "Complete Project A",
                StartDate = new DateTime(2009, 7, 17), EndDate = new DateTime(2009, 7, 10) });
            data.Add(new Task() { TaskName = "Test Website",
                StartDate = new DateTime(2009, 7, 10), EndDate = new DateTime(2009, 7, 12) });
            data.Add(new Task() { TaskName = "Publish Docs",
                StartDate = new DateTime(2009, 7, 4), EndDate = new DateTime(2009, 7, 6) });
            return data;

    public class Task : IDXDataErrorInfo {
        public string TaskName { get; set; }
        public DateTime StartDate { get; set; }
        public DateTime EndDate { get; set; }
        void IDXDataErrorInfo.GetError(ErrorInfo info) {
            if (StartDate > EndDate) {
                    "Either StartDate or EndDate should be corrected.",
        void IDXDataErrorInfo.GetPropertyError(string propertyName, ErrorInfo info) {
            switch (propertyName) {
                case "StartDate":
                    if (StartDate > EndDate)
                            "StartDate must be less than EndDate",
                case "EndDate":
                    if (StartDate > EndDate)
                            "EndDate must be greater than StartDate",
                case "TaskName":
                    if (IsStringEmpty(TaskName))
                            "Task name hasn't been entered",
        void SetErrorInfo(ErrorInfo info, string errorText, ErrorType errorType) {
            info.ErrorText = errorText;
            info.ErrorType = errorType;
        bool IsStringEmpty(string str) {
            return (str != null && str.Trim().Length == 0);
See Also