How to add a Label to a DataGridView cell

Question

Is there any way to insert a Label to DataGridView cell at runtime - say for example I wanted a little red number in the top corner of each cell? Do I need to create a new DataGridViewColumn type or can I just add a Label there when I'm populating the DataGridView?

EDIT I am now attempting to do this using Cell painting as per Neolisk's suggestion, but am unsure how to actually get the label to be displayed. I have the following code, where I now add the label text as the cell's Tag before setting its Value :

private void dgvMonthView_CellPainting(object sender, DataGridViewCellPaintingEventArgs e)
{
    DataGridView dgv = this.dgvMonthView;
    DataGridViewCell cell = dgv[e.ColumnIndex, e.RowIndex];

    Label label = new Label();
    label.Text = cell.Tag.ToString();
    label.Font = new Font("Arial", 5);
    label.ForeColor = System.Drawing.Color.Red;
}

Can anyone explain how I can now "attach" label to cell ?

EDIT 2 - Solution I couldn't quite get it to work the above way, so have ended up subclassing the DataGridViewColumn and Cell and overriding the Paint event there to add whatever text is stored in Tag using DrawString rather than a Label as per neolisk's suggestion:

class DataGridViewLabelCell : DataGridViewTextBoxCell
{
    protected override void Paint(Graphics graphics,
                                  Rectangle clipBounds,
                                  Rectangle cellBounds,
                                  int rowIndex,
                                  DataGridViewElementStates cellState,
                                  object value,
                                  object formattedValue,
                                  string errorText,
                                  DataGridViewCellStyle cellStyle,
                                  DataGridViewAdvancedBorderStyle advancedBorderStyle,
                                  DataGridViewPaintParts paintParts)
    {
        // Call the base class method to paint the default cell appearance.
        base.Paint(graphics, clipBounds, cellBounds, rowIndex, cellState,
            value, formattedValue, errorText, cellStyle,
            advancedBorderStyle, paintParts);

        if (base.Tag != null)
        {
            string tag = base.Tag.ToString();
            Point point = new Point(base.ContentBounds.Location.X, base.ContentBounds.Location.Y);
            graphics.DrawString(tag, new Font("Arial", 7.0F), new SolidBrush(Color.Red), cellBounds.X + cellBounds.Width - 15, cellBounds.Y);
        }
    }
}

public class DataGridViewLabelCellColumn : DataGridViewColumn
{
    public DataGridViewLabelCellColumn()
    {
        this.CellTemplate = new DataGridViewLabelCell();
    }
}

Implemented as:

DataGridViewLabelCellColumn col = new DataGridViewLabelCellColumn();
dgv.Columns.Add(col);
col.HeaderText = "Header";
col.Name = "Name"; 

Answer 1

Here is an MSDN tutorial on how to host a control in a Winforms DataGridViewCell.

just follow the procedures of label

Answer 2

maybe this could solve your problem

 class LabelColumn : DataGridViewColumn
{
    public LabelColumn()
        : base(new LabelCell())
    {
    }
    public override DataGridViewCell CellTemplate
    {
        get
        {
            return base.CellTemplate;
        }
        set
        {
            if (value != null &&
            !value.GetType().IsAssignableFrom(typeof(LabelCell)))
            {
                throw new InvalidCastException("Must be a CalendarCell");
            }
            base.CellTemplate = value;
        }
    }
}
public class LabelCell : DataGridViewTextBoxCell
{
    public LabelCell()
        : base()
    {
    }
    public override void InitializeEditingControl(int rowIndex, object initialFormattedValue, DataGridViewCellStyle dataGridViewCellStyle)
    {
        base.InitializeEditingControl(rowIndex, initialFormattedValue, dataGridViewCellStyle);
        LabelEditingControl lb = DataGridView.EditingControl as LabelEditingControl;
        if (this.Value == null)
        {
            lb.Value = this.DefaultNewRowValue;
        }
        else
        {
            lb.Value = this.Value;
        }
    }
    public override Type EditType
    {
        get
        {
            // Return the type of the editing control that CalendarCell uses.
            return typeof(LabelEditingControl);
        }
    }

    public override Type ValueType
    {
        get
        {
            // Return the type of the value that CalendarCell contains.

            return typeof(string);
        }
    }
    public override object DefaultNewRowValue
    {
        get
        {
            // Use the "".
            return "";
        }
    }
    class LabelEditingControl : Label, IDataGridViewEditingControl
    {
        DataGridView dataGridView;
        private bool valueChanged = false;
        int rowIndex;
        public Object Value { get; set; }
        public LabelEditingControl()
        {
            this.Enabled = false;
        }
        public object EditingControlFormattedValue
        {
            get
            {
                return this.Value.ToString();
            }
            set
            {
                if (value is String)
                {
                    try
                    {
                        // This will throw an exception of the string is 
                        // null, empty, or not in the format of a date.
                        this.Value = value;
                    }
                    catch
                    {
                        // In the case of an exception, just use the 
                        // default value so we're not left with a null
                        // value.
                        this.Value = "";
                    }
                }
            }
        }
        public object GetEditingControlFormattedValue(DataGridViewDataErrorContexts context)
        {
            return EditingControlFormattedValue;
        }
        public void ApplyCellStyleToEditingControl(
    DataGridViewCellStyle dataGridViewCellStyle)
        {
            this.Font = dataGridViewCellStyle.Font;
            this.ForeColor = dataGridViewCellStyle.ForeColor;
            this.BackColor = dataGridViewCellStyle.BackColor;
        }
        public int EditingControlRowIndex
        {
            get
            {
                return rowIndex;
            }
            set
            {
                rowIndex = value;
            }
        }
        public bool EditingControlWantsInputKey(
   Keys key, bool dataGridViewWantsInputKey)
        {
            // Let the DateTimePicker handle the keys listed.
            switch (key & Keys.KeyCode)
            {
                case Keys.Left:
                case Keys.Up:
                case Keys.Down:
                case Keys.Right:
                case Keys.Home:
                case Keys.End:
                case Keys.PageDown:
                case Keys.PageUp:
                    return true;
                default:
                    return !dataGridViewWantsInputKey;
            }
        }

        // Implements the IDataGridViewEditingControl.PrepareEditingControlForEdit 
        // method.
        public void PrepareEditingControlForEdit(bool selectAll)
        {
            // No preparation needs to be done.
        }
        public bool RepositionEditingControlOnValueChange
        {
            get
            {
                return false;
            }
        }

        // Implements the IDataGridViewEditingControl
        // .EditingControlDataGridView property.
        public DataGridView EditingControlDataGridView
        {
            get
            {
                return dataGridView;
            }
            set
            {
                dataGridView = value;
            }
        }

        // Implements the IDataGridViewEditingControl
        // .EditingControlValueChanged property.
        public bool EditingControlValueChanged
        {
            get
            {
                return valueChanged;
            }
            set
            {
                valueChanged = value;
            }
        }

        // Implements the IDataGridViewEditingControl
        // .EditingPanelCursor property.
        public Cursor EditingPanelCursor
        {
            get
            {
                return base.Cursor;
            }
        }

    }
}

on form write this code

 LabelColumn clm = new LabelColumn();
        dataGridView1.Columns.Add(clm);
        dataGridView1.Rows.Add(5);
        foreach (DataGridViewRow row in this.dataGridView1.Rows)
        {
            row.Cells[0].Value ="hello"; //or do anything desired
        }

Answer 3

If you are doing custom painting, you should be using Graphics.DrawString instead of Label control. Your e is of type DataGridViewCellPaintingEventArgs , so it has Graphics property. Here is an example of using PaintEventArgs , yours should be similar.