可以将文章内容翻译成中文,广告屏蔽插件可能会导致该功能失效(如失效，请关闭广告屏蔽插件后再试):

问题:

I have a DataGridView which was the subject of a previous question (link). But sometimes the Button is null. This is fine. But if it is null, is there any way I can optionally remove/add (show/hide?) buttons to the DataGridViewButtonColumn of Buttons

like this:

+------------+------------+
| MyText     | MyButton   |
+------------+------------+
| "do this"  | (Yes)      |
| "do that"  | (Yes)      |
| FYI 'blah' |            | <---- this is where I optionally want no button
| "do other" | (Yes)      |
+------------+------------+

this is what I have tried so far (based on this example)

private void grdVerdict_CellFormat(object sender, DataGridViewCellFormattingEventArgs e)
{
   if (e.ColumnIndex == grdChoice.Columns["yesbutton"].Index)
   {
       if (grdVerdict[e.ColumnIndex, e.RowIndex].Value == null)
       {
            //grdVerdict[e.ColumnIndex, e.RowIndex].Visible = false; //<-says 'it is read only'
            //grdVerdict[e.ColumnIndex, e.RowIndex].Value = new DataGridTextBox(); //<- draws 'mad red cross' over whole grid
            //((Button)grdVerdict[e.ColumnIndex, e.RowIndex]).Hide; //<- won't work
       }
       else
       {
          e.Value = ((Button)grdChoice[e.ColumnIndex, e.RowIndex].Value).Text;
       }
   }
}

回答1:

I had the same "problem" today. I also wanted to hide buttons of certain rows. After playing around with it for a while, I discovered a very simple and nice solution, that doesn't require any overloaded paint()-functions or similar stuff:

Just assign a different DataGridViewCellStyle to those cells.
The key is, that you set the padding property of this new style to a value that shifts the whole button out of the visible area of the cell.
That's it! :-)

Sample:

System::Windows::Forms::DataGridViewCellStyle^  dataGridViewCellStyle2 = (gcnew System::Windows::Forms::DataGridViewCellStyle());
dataGridViewCellStyle2->Padding = System::Windows::Forms::Padding(25, 0, 0, 0);

dgv1->Rows[0]->Cells[0]->Style = dataGridViewCellStyle2;
// The width of column 0 is 22.
// Instead of fixed 25, you could use `columnwidth + 1` also.

回答2:

Padding didn't work for me. I think it is easier and cleaner to just make the cell an empty text cell. VB, but you get the idea:

Dim oEmptyTextCell As New DataGridViewTextBoxCell()
oEmptyTextCell.Value = String.Empty
oRow.Cells(i) = oEmptyTextCell

回答3:

You can disabled a DataGridViewButton with a little effort as suggested in this post: Disabling the button column in the datagridview

I preferred using a DataGridViewImageColumn and DataGridView.CellFormatting event to display different pictures as an image button could be enabled or not.

In this case, if button must be disabled you can display a blank image and do nothing on DataGridView.CellClick event.

回答4:

Based on Tobias' answer I made a small static helper method to hide the contents of the cell by adjusting it's padding.

Be aware though that the button is still "clickable" in that if the user selects the cell and presses space it clicks the hidden button, so I check that the cell's value is not readonly before I process any clicks in my contentclick event

  public static void DataGridViewCellVisibility(DataGridViewCell cell, bool visible)
  {
        cell.Style = visible ?
              new DataGridViewCellStyle { Padding = new Padding(0, 0, 0, 0) } :
              new DataGridViewCellStyle { Padding = new Padding(cell.OwningColumn.Width, 0, 0, 0) };

        cell.ReadOnly = !visible;
  }

回答5:

As an improvement to Sriram's answer, I would suggest just overriding the cell painting event and only painting the background. I found that painting a textbox made it look a little odd.

void dataGridView1_CellPainting(object sender, DataGridViewCellPaintingEventArgs e) { if (e.ColumnIndex == yourColumnIndex && String.IsNullOrEmpty((string)e.FormattedValue)) { e.PaintBackground(e.ClipBounds, true); e.Handled = true; } }

回答6:

Handle custom painting and paint a textbox over there.

void dataGridView1_CellPainting(object sender, DataGridViewCellPaintingEventArgs e)
{
    if (e.ColumnIndex == yourColumnIndex && String.IsNullOrEmpty((string)e.FormattedValue))
    {
        Graphics g = e.Graphics;
        TextBoxRenderer.DrawTextBox(g, e.CellBounds,
            System.Windows.Forms.VisualStyles.TextBoxState.Normal);
        e.Handled = true;
    }
}