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DataGridViewCellValueEventArgs Class

  • Reference

Definition

Namespace:
System.Windows.Forms
Assembly:
System.Windows.Forms.dll

Provides data for the CellValueNeeded and CellValuePushed events of the DataGridView control.

public ref class DataGridViewCellValueEventArgs : EventArgs
public class DataGridViewCellValueEventArgs : EventArgs
type DataGridViewCellValueEventArgs = class
    inherit EventArgs
Public Class DataGridViewCellValueEventArgs
Inherits EventArgs
Inheritance
Object
EventArgs
DataGridViewCellValueEventArgs

Examples

The following code example handles the CellValuePushed event to store updates and new entries in a data store object. This example is part of a larger example available in the DataGridView.VirtualMode reference topic.

#pragma region Data store maintance

    void VirtualConnector::dataGridView1_CellValueNeeded
        (Object^ sender, DataGridViewCellValueEventArgs^ e)
    {
        if (store->ContainsKey(e->RowIndex))
        {
            // Use the store if the e value has been modified 
            // and stored.            
            e->Value = gcnew Int32(store->default[e->RowIndex]); 
        }
        else if (newRowNeeded && e->RowIndex == numberOfRows)
        {
            if (dataGridView1->IsCurrentCellInEditMode)
            {
                e->Value = initialValue;
            }
            else
            {
                // Show a blank e if the cursor is just loitering
                // over(the) last row.
                e->Value = String::Empty;
            }
        }
        else
        {
            e->Value = e->RowIndex;
        }
    }

    void VirtualConnector::dataGridView1_CellValuePushed
        (Object^ sender, DataGridViewCellValueEventArgs^ e)
    {
        String^ value = e->Value->ToString();
        store[e->RowIndex] = Int32::Parse(value, 
            CultureInfo::CurrentCulture);
    }
#pragma endregion

#region "data store maintance"
const int initialValue = -1;

private void dataGridView1_CellValueNeeded(object sender,
    DataGridViewCellValueEventArgs e)
{
    if (store.ContainsKey(e.RowIndex))
    {
        // Use the store if the e value has been modified 
        // and stored.            
        e.Value = store[e.RowIndex];
    }
    else if (newRowNeeded && e.RowIndex == numberOfRows)
    {
        if (dataGridView1.IsCurrentCellInEditMode)
        {
            e.Value = initialValue;
        }
        else
        {
            // Show a blank value if the cursor is just resting
            // on the last row.
            e.Value = String.Empty;
        }
    }
    else
    {
        e.Value = e.RowIndex;
    }
}

private void dataGridView1_CellValuePushed(object sender,
    DataGridViewCellValueEventArgs e)
{
    store.Add(e.RowIndex, int.Parse(e.Value.ToString()));
}
#endregion

private Dictionary<int, int> store = new Dictionary<int, int>();

#Region "data store maintance"
    Const initialValue As Integer = -1

    Private Sub dataGridView1_CellValueNeeded(ByVal sender As Object, _
        ByVal e As DataGridViewCellValueEventArgs) _
        Handles dataGridView1.CellValueNeeded

        If store.ContainsKey(e.RowIndex) Then
            ' Use the store if the e value has been modified 
            ' and stored.
            e.Value = store(e.RowIndex)
        ElseIf newRowNeeded AndAlso e.RowIndex = numberOfRows Then
            If dataGridView1.IsCurrentCellInEditMode Then
                e.Value = initialValue
            Else
                ' Show a blank value if the cursor is just resting
                ' on the last row.
                e.Value = String.Empty
            End If
        Else
            e.Value = e.RowIndex
        End If
    End Sub

    Private Sub dataGridView1_CellValuePushed(ByVal sender As Object, _
        ByVal e As DataGridViewCellValueEventArgs) _
        Handles dataGridView1.CellValuePushed

        store.Add(e.RowIndex, CInt(e.Value))

    End Sub
#End Region

    Dim store As System.Collections.Generic.Dictionary(Of Integer, Integer) = _
        New Dictionary(Of Integer, Integer)

Remarks

Handle the CellValueNeeded and CellValuePushed events to implement virtual mode in the DataGridView control. For more information about virtual mode, see Virtual Mode in the Windows Forms DataGridView Control.

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

Constructors

DataGridViewCellValueEventArgs(Int32, Int32)

Initializes a new instance of the DataGridViewCellValueEventArgs class.

Properties

ColumnIndex

Gets a value indicating the column index of the cell that the event occurs for.
RowIndex

Gets a value indicating the row index of the cell that the event occurs for.
Value

Gets or sets the value of the cell that the event occurs for.

Methods

Equals(Object)

Determines whether the specified object is equal to the current object.

(Inherited from Object)
GetHashCode()

Serves as the default hash function.

(Inherited from Object)
GetType()

Gets the Type of the current instance.

(Inherited from Object)
MemberwiseClone()

Creates a shallow copy of the current Object.

(Inherited from Object)
ToString()

Returns a string that represents the current object.

(Inherited from Object)

Applies to

See also