ColumnView.CellValueChanging Event

Fires when a user changes a cell value: types or deletes a character, chooses a value from the dropdown list, etc. Does not fire when you change cell values in code.

Namespace: DevExpress.XtraGrid.Views.Base

Assembly: DevExpress.XtraGrid.v20.1.dll

Declaration

[DXCategory("Property Changed")]
public event CellValueChangedEventHandler CellValueChanging
<DXCategory("Property Changed")>
Public Event CellValueChanging As CellValueChangedEventHandler

Event Data

The CellValueChanging event's data class is CellValueChangedEventArgs. The following properties provide information specific to this event:

Property Description
Column Gets the column that contains the processed cell.
RowHandle Gets the handle of the row that contains the processed cell.
Value Gets the current cell value.

Remarks

The code sample below illustrates how to highlight edited cells.

CV_CellValueChanging


using DevExpress.XtraGrid.Views.Grid;
using DevExpress.XtraGrid.Views.Base;
using DevExpress.XtraGrid.Columns;

public partial class Form1 : Form {
    List<GridChangedCellInfo> changedCells;
    public Form1() {
        InitializeComponent();
        changedCells = new List<GridChangedCellInfo>();
        gridControl1.DataSource = new List<Person> {
            new Person() { ID=1, Name="John Doe", Text="Comments Line 1" },
            new Person() { ID=2, Name="Jill Jones", Text="Comments Line 2" },
            new Person() { ID=3, Name="Cyril James", Text="Comments Line 3" },
        };
        gridView1.CellValueChanging += gridView1_CellValueChanging;
        gridView1.CustomDrawCell += GridView1_CustomDrawCell;
    }
    void gridView1_CellValueChanging(object sender, CellValueChangedEventArgs e)
    {
        var view = sender as GridView;
        var listSourceRowIndex = view.GetDataSourceRowIndex(e.RowHandle);
        var changedCell = new GridChangedCellInfo(listSourceRowIndex, e.Column);
        if (!changedCells.Contains(changedCell))
            changedCells.Add(changedCell);
    }
    private void GridView1_CustomDrawCell(object sender, RowCellCustomDrawEventArgs e)
    {
        var view = sender as GridView;
        var listSourceRowIndex = view.GetDataSourceRowIndex(e.RowHandle);
        var changedCell = new GridChangedCellInfo(listSourceRowIndex, e.Column);

        if (!changedCells.Contains(changedCell))
            return;
        e.Appearance.BackColor = Color.Red;
        e.Appearance.DrawBackground(e.Cache, e.Bounds);
        e.Appearance.DrawString(e.Cache, e.DisplayText, e.Bounds);
        e.Handled = true;
    }
}
public class GridChangedCellInfo
{
    public int ListSourceRowIndex { get; set; }
    public GridColumn Column { get; set; }
    public GridChangedCellInfo(int listSourceRowIndex, GridColumn column)
    {
        ListSourceRowIndex = listSourceRowIndex;
        Column = column;
    }

    public override bool Equals(object obj)
    {
        if (!(obj is GridChangedCellInfo))
            return false;

        var gridChangedCellInfo = obj as GridChangedCellInfo;

        return Column.Equals(gridChangedCellInfo.Column)
            && ListSourceRowIndex.Equals(gridChangedCellInfo.ListSourceRowIndex);
    }
    public override int GetHashCode()
    {
        return base.GetHashCode();
    }
}
public class Person {
    public int ID { get; set; }
    public string Name { get; set; }
    public string Text { get; set; }
}
See Also