How to remove the top-right corner error mark from the GridCell in WinRT DataGird?

2 mins read

In the SfDataGrid, validation can be done by handling the CurrentCellValidating event. The SfDataGrid does not allow the end-user to move to the other cells until the validation succeeds. In a meantime, you can move to the other cells after pressing Esc key that resets the validation status and error message at the top-right corner.

//Handles the CurrentCellValidating event.
SfdataGrid.CurrentCellValidating += SfdataGrid_CurrentCellValidating;
void SfdataGrid_CurrentCellValidating(object sender, CurrentCellValidatingEventArgs args)
{
    if (args.Column.MappingName == "EmployeeSalary" && Convert.ToDouble(args.NewValue) < 20000)
    {
        args.ErrorMessage = "EmployeeSalary should not less than 20000";
        args.IsValid = false;
    }
}

It is possible to reset the validation status when the end-user presses Esc key from the edit mode by overriding the GridSelectionController. In the following code example, the validation status and top-right corner error indication is reset by invoking the ValidationHelper.ResetValidations method on pressing the Esc key by overriding the ProcessKeyDown method of the GridSelectionController.

For WPF:

using Syncfusion.UI.Xaml.Grid;
using Syncfusion.UI.Xaml.Grid.Helpers;
// Sets the instance of the customized GridSelectionController class to the SfDataGird.SelectionController property.
SfdataGrid.SelectionController = new GridSelectionControllerExt(SfdataGrid);
public class GridSelectionControllerExt : GridSelectionController
{
    public GridSelectionControllerExt(SfDataGrid dataGrid)
        : base(dataGrid)
    {
    }
    protected override void ProcessKeyDown(KeyEventArgs args)
    {
        if (this.CurrentCellManager.HasCurrentCell && this.CurrentCellManager.CurrentCell.IsEditing && args.Key == Key.Escape)
        {
            var helper = DataGrid.GetValidationHelper();
            MethodInfo[] methodInfos = typeof(ValidationHelper).GetMethods(BindingFlags.NonPublic | BindingFlags.Instance);
            // Gets the ResetValidations method by using reflection.
            var resetValidation = methodInfos.FirstOrDefault(item => item.Name == "ResetValidations");
            resetValidation.Invoke(helper, new object[] { true });
            this.CurrentCellManager.EndEdit(false);
            return;
        }
        base.ProcessKeyDown(args);
    }
}

For WinRT:

public class GridSelectionControllerExt : GridSelectionController
{
    public GridSelectionControllerExt(SfDataGrid dataGrid)
        : base(dataGrid)
    {
    }
    protected override void ProcessKeyDown(KeyRoutedEventArgs args)
    {     
        if (this.CurrentCellManager.HasCurrentCell && this.CurrentCellManager.CurrentCell.IsEditing && args.Key == VirtualKey.Escape)
        {
            var helper = DataGrid.GetValidationHelper();
            // Gets the ResetValidations method by using reflection.
            foreach (var method in helper.GetType().GetRuntimeMethods())
            {
                if (method.Name.Equals("ResetValidations"))
                {
                    method.Invoke(helper, new object[] { true });
                    this.CurrentCellManager.EndEdit(false);
                    return;
                }
            }      
        }
        base.ProcessKeyDown(args);
    }
}

Note:

You need to override the GridCellSelectionController class when the SelectionUnit is GridSelecionUnit.Cell.

The corner error mark is enabled when the employeesalary less 20000 as shown in following screenshot

employeeSalary