DataGridView.CellMouseEnter 事件

定义

命名空间:

System.Windows.Forms

程序集:

System.Windows.Forms.dll

鼠标指针进入单元格时发生。

public:
 event System::Windows::Forms::DataGridViewCellEventHandler ^ CellMouseEnter;

public event System.Windows.Forms.DataGridViewCellEventHandler CellMouseEnter;

member this.CellMouseEnter : System.Windows.Forms.DataGridViewCellEventHandler 

Public Custom Event CellMouseEnter As DataGridViewCellEventHandler 

事件类型

DataGridViewCellEventHandler

示例

下面的代码示例演示 CellMouseEnter Tic-Tac-Toe 游戏实现中的事件处理程序，该处理程序使用 控件中的 DataGridView 图像列。 事件处理程序使用单元格值来确定要显示的光标和工具提示。

此代码是How to： Work with Image Columns in the Windows 窗体 DataGridView 控件中显示的较大示例的一部分。

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

注解

有关如何处理事件的详细信息，请参阅 处理和引发事件。

另请参阅

• DataGridView 控件（Windows 窗体）