SpreadsheetControl.CellBeginEdit Event

Occurs before a cell editor is opened.

Namespace: DevExpress.XtraSpreadsheet

Assembly: DevExpress.XtraSpreadsheet.v24.1.dll

NuGet Package: DevExpress.Win.Spreadsheet

Declaration

C#

public event CellBeginEditEventHandler CellBeginEdit

VB.NET

Public Event CellBeginEdit As CellBeginEditEventHandler

Event Data

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

Property	Description
Cancel	Gets or sets whether the operation performed on the processed event should be canceled.
Cell	Gets the cell for which the event is fired. Inherited from SpreadsheetCellEventArgsBase.
ColumnIndex	Gets the index of the column that contains the cell. Inherited from SpreadsheetCellEventArgsBase.
Formula	Gets the formula that is currently contained in the cell. Inherited from SpreadsheetCellEventArgsBase.
FormulaInvariant	Gets the formula in the invariant culture that is currently contained in the cell. Inherited from SpreadsheetCellEventArgsBase.
RowIndex	Gets the index of the row that contains the cell. Inherited from SpreadsheetCellEventArgsBase.
SheetName	Gets the name of the worksheet that contains the cell. Inherited from SpreadsheetCellEventArgsBase.
Value	Gets the value currently contained in the cell. Inherited from SpreadsheetCellEventArgsBase.
Worksheet	Gets the worksheet that contains the cell. Inherited from SpreadsheetCellEventArgsBase.

Remarks

Handle the CellBeginEdit event to perform any actions when a user activates a cell editor (the in-place editor or formula bar).

Use the Cell parameter to access a cell for which the cell editor is opened. The Value and Formula parameters return a value and formula currently contained in this cell.

To prevent a user from editing a cell value, handle this event and set its Cancel parameter to true.

After a cell editor is activated, the SpreadsheetControl.CellEditorOpened event fires. The SpreadsheetControl.CellEndEdit or SpreadsheetControl.CellCancelEdit event occurs before a cell editor is closed, depending on whether the entered value is committed to a cell or rolled back.

Example

The example below shows how to validate user input for a sample spreadsheet:

The following events are used to perform this task:

• SpreadsheetControl.CellBeginEdit

  Handle this event to specify that a user can edit cells only in the “Unit Price” and “Units in Stock” columns.

• SpreadsheetControl.CellEndEdit

  This event validates a value that a user enters into a cell. If the entered value is not a valid number, the Spreadsheet cancels the input and displays a warning.

• SpreadsheetControl.CellValueChanged

  If a cell value in the “Units in Stock” column is equal to zero, the cell’s background color changes to light pink.

C#

using DevExpress.Spreadsheet;
using DevExpress.XtraSpreadsheet;
using System.Drawing;
using System.Globalization;
using System.Windows.Forms;
// ...

public partial class Form1 : DevExpress.XtraBars.Ribbon.RibbonForm
{
    public Form1()
    {
        InitializeComponent();
        spreadsheetControl1.CellBeginEdit += SpreadsheetControl1_CellBeginEdit;
        spreadsheetControl1.CellEndEdit += SpreadsheetControl1_CellEndEdit;
        spreadsheetControl1.CellValueChanged += SpreadsheetControl1_CellValueChanged;

        IWorkbook workbook = spreadsheetControl1.Document;
        workbook.LoadDocument("Products.xlsx", DocumentFormat.Xlsx);

    }

    private CultureInfo CurrentCulture => spreadsheetControl1.Options.Culture;

    private void SpreadsheetControl1_CellBeginEdit(object sender, SpreadsheetCellCancelEventArgs e)
    {
        // Allow users to edit cells only in the 'Unit Price' and 'Units in Stock' columns.
        if (e.Cell.ColumnIndex < 2 || e.Cell.ColumnIndex > 3 || e.Cell.RowIndex < 1 || e.Cell.RowIndex > 19)
        {
            e.Cancel = true;
            MessageBox.Show("You can edit only the 'Unit Price' and 'Units in Stock' values.", "Warning", MessageBoxButtons.OK);
        }
    }

    private void SpreadsheetControl1_CellEndEdit(object sender, SpreadsheetCellValidatingEventArgs e)
    {
        // Validate a value that a user enters into a cell.
        string editorText = e.EditorText;
        bool validValue = e.Cell.ColumnIndex == 2 ? ValidateUnitPrice(editorText) : ValidateUnitsInStock(editorText);
        if (!validValue)
        {
            e.Cancel = true;
            MessageBox.Show("The value you entered is invalid.", "Warning", MessageBoxButtons.OK);
        }
    }

    private bool ValidateUnitPrice(string text)
    {
        // Validate values in the 'Unit Price' column.
        // Convert the obtained string to a Double value. 
        bool conversionResult = double.TryParse(text, NumberStyles.AllowDecimalPoint, CurrentCulture, out double result);
        return conversionResult && result > 0;
    }

    private bool ValidateUnitsInStock(string text)
    {
        // Validate values in the 'Units in Stock' column.
        // Convert the obtained string to an integer value. 
        return int.TryParse(text, NumberStyles.None, CurrentCulture, out int result);
    }

    private void SpreadsheetControl1_CellValueChanged(object sender, SpreadsheetCellEventArgs e)
    {
        if (e.Cell.ColumnIndex != 3)
            return;
        // Highlight zero values in the 'Units in Stock' column.
        e.Cell.FillColor = (e.Value.NumericValue == 0) ? Color.LightPink : Color.White;
    }
}

VB.NET

Imports DevExpress.Spreadsheet
Imports DevExpress.XtraSpreadsheet
Imports System.Drawing
Imports System.Globalization
Imports System.Windows.Forms
' ...

Partial Public Class Form1
    Inherits DevExpress.XtraBars.Ribbon.RibbonForm
    Public Sub New()
        InitializeComponent()
        AddHandler spreadsheetControl1.CellBeginEdit, AddressOf SpreadsheetControl1_CellBeginEdit
        AddHandler spreadsheetControl1.CellEndEdit, AddressOf SpreadsheetControl1_CellEndEdit
        AddHandler spreadsheetControl1.CellValueChanged, AddressOf SpreadsheetControl1_CellValueChanged

        Dim workbook As IWorkbook = spreadsheetControl1.Document
        workbook.LoadDocument("Products.xlsx", DocumentFormat.Xlsx)
    End Sub

    Private ReadOnly Property CurrentCulture() As CultureInfo
        Get
            Return spreadsheetControl1.Options.Culture
        End Get
    End Property

    Private Sub SpreadsheetControl1_CellBeginEdit(ByVal sender As Object, ByVal e As SpreadsheetCellCancelEventArgs)
        ' Allow users to edit cells only in the 'Unit Price' and 'Units in Stock' columns.
        If e.Cell.ColumnIndex < 2 OrElse e.Cell.ColumnIndex > 3 OrElse e.Cell.RowIndex < 1 OrElse e.Cell.RowIndex > 19 Then
            e.Cancel = True
            MessageBox.Show("You can edit only the 'Unit Price' and 'Units in Stock' values.", "Warning", MessageBoxButtons.OK)
        End If
    End Sub

    Private Sub SpreadsheetControl1_CellEndEdit(ByVal sender As Object, ByVal e As SpreadsheetCellValidatingEventArgs)
        ' Validate a value that a user enters into a cell.
        Dim editorText As String = e.EditorText
        Dim validValue As Boolean = If(e.Cell.ColumnIndex = 2, ValidateUnitPrice(editorText), ValidateUnitsInStock(editorText))
        If Not validValue Then
            e.Cancel = True
            MessageBox.Show("The value you entered is invalid.", "Warning", MessageBoxButtons.OK)
        End If
    End Sub

    Private Function ValidateUnitPrice(ByVal text As String) As Boolean
        ' Validate values in the 'Unit Price' column.
        ' Convert the obtained string to a Double value.
        Dim result As Double
        Dim conversionResult As Boolean = Double.TryParse(text, NumberStyles.AllowDecimalPoint, CurrentCulture, result)
        Return conversionResult AndAlso result > 0
    End Function

    Private Function ValidateUnitsInStock(ByVal text As String) As Boolean
        ' Validate values in the 'Units in Stock' column.
        ' Convert the obtained string to an integer value.
        Dim result As Integer
        Return Integer.TryParse(text, NumberStyles.None, CurrentCulture, result)
    End Function

    Private Sub SpreadsheetControl1_CellValueChanged(ByVal sender As Object, ByVal e As SpreadsheetCellEventArgs)
        If e.Cell.ColumnIndex <> 3 Then
            Return
        End If
        ' Highlight zero values in the 'Units in Stock' column.
        e.Cell.FillColor = If(e.Value.NumericValue = 0, Color.LightPink, Color.White)
    End Sub

End Class