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DataGridViewCellEventHandler Delegate

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Definition

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

Represents the method that will handle DataGridView events related to cell and row operations.

public delegate void DataGridViewCellEventHandler(System::Object ^ sender, DataGridViewCellEventArgs ^ e);
public delegate void DataGridViewCellEventHandler(object sender, DataGridViewCellEventArgs e);
public delegate void DataGridViewCellEventHandler(object? sender, DataGridViewCellEventArgs e);
type DataGridViewCellEventHandler = delegate of obj * DataGridViewCellEventArgs -> unit
Public Delegate Sub DataGridViewCellEventHandler(sender As Object, e As DataGridViewCellEventArgs)

Parameters

sender
Object

The source of the event.

e
DataGridViewCellEventArgs

A DataGridViewCellEventArgs that contains the event data.

Examples

The following code example demonstrates using CellMouseEnter and CellMouseLeave event handlers to determine whether a cell can be clicked. The example updates each ToolTipText to advertise the current image layout. This code is part of a larger example shown in How to: Work with Image Columns in the Windows Forms DataGridView Control.

void dataGridView1_CellMouseEnter( Object^ sender, DataGridViewCellEventArgs^ e )
{
   Bitmap^ markingUnderMouse = dynamic_cast<Bitmap^>(dataGridView1->Rows[ e->RowIndex ]->Cells[ e->ColumnIndex ]->Value);
   if ( markingUnderMouse == blank )
   {
      dataGridView1->Cursor = Cursors::Default;
   }
   else
   if ( markingUnderMouse == o || markingUnderMouse == x )
   {
      dataGridView1->Cursor = Cursors::No;
      ToolTip(e,true);
   }
}

void ToolTip( DataGridViewCellEventArgs^ e, bool showTip )
{
   DataGridViewImageCell^ cell = dynamic_cast<DataGridViewImageCell^>(dataGridView1->Rows[ e->RowIndex ]->Cells[ e->ColumnIndex ]);
   DataGridViewImageColumn^ imageColumn = dynamic_cast<DataGridViewImageColumn^>(dataGridView1->Columns[ cell->ColumnIndex ]);
   if ( showTip )
         cell->ToolTipText = imageColumn->Description;
   else
   {
      cell->ToolTipText = String::Empty;
   }
}

void dataGridView1_CellMouseLeave( Object^ sender, DataGridViewCellEventArgs^ e )
{
   ToolTip( e, false );
   dataGridView1->Cursor = Cursors::Default;
}

private void dataGridView1_CellMouseEnter(object sender,
    DataGridViewCellEventArgs e)
{
    Bitmap markingUnderMouse = (Bitmap)dataGridView1.
           Rows[e.RowIndex].
           Cells[e.ColumnIndex].Value;

    if (markingUnderMouse == blank)
    {
        dataGridView1.Cursor = Cursors.Default;
    }
    else if (markingUnderMouse == o || markingUnderMouse == x)
    {
        dataGridView1.Cursor = Cursors.No;
        ToolTip(e, true);
    }
}

private void ToolTip(DataGridViewCellEventArgs e, bool showTip)
{
    DataGridViewImageCell cell = (DataGridViewImageCell)
        dataGridView1
        .Rows[e.RowIndex].Cells[e.ColumnIndex];
    DataGridViewImageColumn imageColumn =
        (DataGridViewImageColumn)
        dataGridView1.Columns[cell.ColumnIndex];

    if (showTip)
    {
        cell.ToolTipText = imageColumn.Description;
    }
    else { cell.ToolTipText = String.Empty; }
}

private void dataGridView1_CellMouseLeave(object sender,
    DataGridViewCellEventArgs e)
{
    ToolTip(e, false);
    dataGridView1.Cursor = Cursors.Default;
}

Private Sub dataGridView1_CellMouseEnter(ByVal sender As Object, _
    ByVal e As DataGridViewCellEventArgs) _
    Handles dataGridView1.CellMouseEnter

    Dim markingUnderMouse As Bitmap = _
        CType(dataGridView1.Rows(e.RowIndex). _
            Cells(e.ColumnIndex).Value, Bitmap)

    If markingUnderMouse Is blank Then
        dataGridView1.Cursor = Cursors.Default
    ElseIf markingUnderMouse Is o OrElse markingUnderMouse Is x Then
        dataGridView1.Cursor = Cursors.No
        ToolTip(e)
    End If
End Sub

Private Sub ToolTip( _
    ByVal e As DataGridViewCellEventArgs)

    Dim cell As DataGridViewImageCell = _
        CType(dataGridView1.Rows(e.RowIndex). _
        Cells(e.ColumnIndex), DataGridViewImageCell)
    Dim imageColumn As DataGridViewImageColumn = _
        CType(dataGridView1.Columns(cell.ColumnIndex), _
        DataGridViewImageColumn)

    cell.ToolTipText = imageColumn.Description
End Sub

Private Sub dataGridView1_CellMouseLeave(ByVal sender As Object, _
    ByVal e As DataGridViewCellEventArgs) _
    Handles dataGridView1.CellMouseLeave

    dataGridView1.Cursor = Cursors.Default
End Sub

Remarks

DataGridViewCellEventHandler handles the following DataGridView events:

When you create a DataGridViewCellEventHandler delegate, you identify the method that will handle the event. To associate the event with your event handler, add an instance of the delegate to the event. The event handler is called whenever the event occurs, unless you remove the delegate. For more information about event-handler delegates, see Handling and Raising Events.

Extension Methods

GetMethodInfo(Delegate)

Gets an object that represents the method represented by the specified delegate.

Applies to

See also