this.dg.AutoGenerateColumns = false;

DataGridViewCheckBoxColumn chkcol = new DataGridViewCheckBoxColumn();
chkcol.AutoSizeMode = DataGridViewAutoSizeColumnMode.AllCellsExceptHeader;
chkcol.ValueType = typeof(bool);
chkcol.FalseValue = false;
chkcol.TrueValue = true;

// PROBLEM HERE

chkcol.CellTemplate.Value = true;

// END PROBLEM

this.dg.Columns.Add(chkcol);

Well, I can see the column; however, when adding a new row to the DataGridView, the .Valueof the new cell is always null; as such, my new row does not have a check box in the newly added row. I know I could add a handler on the "RowsAdded" event and set the .Value there, but I thought the cell template would handle this by setting the .Value of the new cell to true. It does not. Can anyone tell me why the new value of the cell is always null although I have defined the CellTemplate.Value to be true? Thank you.

Trecius

Hi,

Changing the properties of the cell template will not immediately affect the user interface (UI) of the column's existing cells. These changes are only apparent after the column is regenerated (for example, by sorting the column or through a call to the DataGridView.InvalidateColumn method). (From DataGridViewCheckBoxColumn.CellTemplate Property msdn document)

For unbound column, you’d better set the value in DataGridView_DefaultValueNeed event.

        void dataGridView1_DefaultValuesNeeded(object sender, DataGridViewRowEventArgs e)

        {

            e.Row.Cells["checkColumn"].Value = true;

        }

Or set the DefaultCellStyle.NullValue.

chkcolumn.DefaultCellStyle.NullValue = true;

Then you can get the true value by

dataGridView1.CurrentRow.Cells["checkColumn"].FormattedValue property.

Best regards,

Ling Wang

Hi,

Changing the properties of the cell template will not immediately affect the user interface (UI) of the column's existing cells. These changes are only apparent after the column is regenerated (for example, by sorting the column or through a call to the DataGridView.InvalidateColumn method). (From DataGridViewCheckBoxColumn.CellTemplate Property msdn document)

For unbound column, you’d better set the value in DataGridView_DefaultValueNeed event.

        void dataGridView1_DefaultValuesNeeded(object sender, DataGridViewRowEventArgs e)

        {

            e.Row.Cells["checkColumn"].Value = true;

        }

Or set the DefaultCellStyle.NullValue.

chkcolumn.DefaultCellStyle.NullValue = true;

Then you can get the true value by

dataGridView1.CurrentRow.Cells["checkColumn"].FormattedValue property.

Best regards,

Ling Wang