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DataGridView.CellValueChanged Event

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Definition

Namespace:
System.Windows.Forms
Assembly:
System.Windows.Forms.dll
Source:
DataGridView.cs
Source:
DataGridView.cs
Source:
DataGridView.cs

Occurs when the value of a cell changes.

public:
 event System::Windows::Forms::DataGridViewCellEventHandler ^ CellValueChanged;
public event System.Windows.Forms.DataGridViewCellEventHandler CellValueChanged;
public event System.Windows.Forms.DataGridViewCellEventHandler? CellValueChanged;
member this.CellValueChanged : System.Windows.Forms.DataGridViewCellEventHandler 
Public Custom Event CellValueChanged As DataGridViewCellEventHandler

Event Type

DataGridViewCellEventHandler

Examples

The following code example demonstrates how to use the CellValueChanged event to update the values in a balance column of a DataGridView. This example is part of a larger example available in the SelectionChanged event.

private void DataGridView1_CellValueChanged(
    object sender, DataGridViewCellEventArgs e)
{
    // Update the balance column whenever the value of any cell changes.
    UpdateBalance();
}

private void DataGridView1_RowsRemoved(
    object sender, DataGridViewRowsRemovedEventArgs e)
{
    // Update the balance column whenever rows are deleted.
    UpdateBalance();
}

private void UpdateBalance()
{
    int counter;
    int balance;
    int deposit;
    int withdrawal;

    // Iterate through the rows, skipping the Starting Balance row.
    for (counter = 1; counter < (DataGridView1.Rows.Count - 1);
        counter++)
    {
        deposit = 0;
        withdrawal = 0;
        balance = int.Parse(DataGridView1.Rows[counter - 1]
            .Cells["Balance"].Value.ToString());

        if (DataGridView1.Rows[counter].Cells["Deposits"].Value != null)
        {
            // Verify that the cell value is not an empty string.
            if (DataGridView1.Rows[counter]
                .Cells["Deposits"].Value.ToString().Length != 0)
            {
                deposit = int.Parse(DataGridView1.Rows[counter]
                    .Cells["Deposits"].Value.ToString());
            }
        }

        if (DataGridView1.Rows[counter].Cells["Withdrawals"].Value != null)
        {
            if (DataGridView1.Rows[counter]
                .Cells["Withdrawals"].Value.ToString().Length != 0)
            {
                withdrawal = int.Parse(DataGridView1.Rows[counter]
                    .Cells["Withdrawals"].Value.ToString());
            }
        }
        DataGridView1.Rows[counter].Cells["Balance"].Value =
            (balance + deposit + withdrawal).ToString();
    }
}

Private Sub CellValueChanged(ByVal sender As Object, _
    ByVal e As DataGridViewCellEventArgs) _
    Handles DataGridView1.CellValueChanged

    ' Update the balance column whenever the values of any cell changes.
    UpdateBalance()
End Sub

Private Sub RowsRemoved(ByVal sender As Object, _
    ByVal e As DataGridViewRowsRemovedEventArgs) _
    Handles DataGridView1.RowsRemoved

    ' Update the balance column whenever rows are deleted.
    UpdateBalance()
End Sub

Private Sub UpdateBalance()
    Dim counter As Integer
    Dim balance As Integer
    Dim deposit As Integer
    Dim withdrawal As Integer

    ' Iterate through the rows, skipping the Starting Balance Row.
    For counter = 1 To (DataGridView1.Rows.Count - 2)
        deposit = 0
        withdrawal = 0
        balance = Integer.Parse(DataGridView1.Rows(counter - 1) _
            .Cells("Balance").Value.ToString())

        If Not DataGridView1.Rows(counter) _
            .Cells("Deposits").Value Is Nothing Then

            ' Verify that the cell value is not an empty string.
            If Not DataGridView1.Rows(counter) _
                .Cells("Deposits").Value.ToString().Length = 0 Then
                deposit = Integer.Parse(DataGridView1.Rows(counter) _
                    .Cells("Deposits").Value.ToString())
            End If
        End If

        If Not DataGridView1.Rows(counter) _
            .Cells("Withdrawals").Value Is Nothing Then
            If Not DataGridView1.Rows(counter) _
                .Cells("Withdrawals").Value.ToString().Length = 0 Then
                withdrawal = Integer.Parse(DataGridView1.Rows(counter) _
                    .Cells("Withdrawals").Value.ToString())
            End If
        End If

        DataGridView1.Rows(counter).Cells("Balance").Value = _
            (balance + deposit + withdrawal).ToString()
    Next
End Sub

Remarks

The DataGridView.CellValueChanged event occurs when the user-specified value is committed, which typically occurs when focus leaves the cell.

In the case of check box cells, however, you will typically want to handle the change immediately. To commit the change when the cell is clicked, you must handle the DataGridView.CurrentCellDirtyStateChanged event. In the handler, if the current cell is a check box cell, call the DataGridView.CommitEdit method and pass in the Commit value.

Rows in the control are not automatically sorted when a cell value is changed. To sort the control when the user modifies a cell, call the Sort method in a CellValueChanged event handler.

For more information about how to handle events, see Handling and Raising Events.

Applies to

See also