自動送出 Enter

在處理 DataGridView 編輯時，原本使用 GetChanges() 方法，取得 DataTable 中有異動的資料。 再根據其 RowState 決定要 INSERT 或 UPDATE。 但如果使用者編輯後沒有按TAB或ENTER，呼叫 GetChangs() 可能會得到 null 類似這篇 作者是參考這篇解決 測試後依然無解，最後乾脆於儲存時強行 ENTER

SendKeys.SendWait("{ENTER}");

參考這篇，送出字串與按鈕的方法不同。

DataGridView 內使用 DateTimePicker

宣告全域變數

private DateTimePicker cellDateTimePicker;

初始化 Form1() 時加入

this.cellDateTimePicker = new DateTimePicker();
this.cellDateTimePicker.ValueChanged += new EventHandler(cellDateTimePicker_ValueChanged);
//this.cellDateTimePicker.CloseUp += new EventHandler(cellDateTimePicker_CloseUp);
this.cellDateTimePicker.Format = DateTimePickerFormat.Short;
this.cellDateTimePicker.ShowCheckBox = true;
this.cellDateTimePicker.Checked = true;
this.cellDateTimePicker.Visible = false;
this.dgvCertificate.Controls.Add(cellDateTimePicker);

在 ValueChanged 事件加入對應方法 (cellDateTimePicker_ValueChanged)，一些屬性設定。 最後將 DateTimePicker 加入 DataGridView 的 Controls 內 撰寫 cellDateTimePicker_ValueChanged

void cellDateTimePicker_ValueChanged(object sender, EventArgs e)
{
    if (cellDateTimePicker.Checked)
    {
        //cellDateTimePicker.Format = DateTimePickerFormat.Short;
        //cellDateTimePicker.CustomFormat = null;
        dgvCurrent.CurrentCell.Value = cellDateTimePicker.Value.ToString("yyyy/MM/dd"); //convert the date as per your format
    }
    else
    {
        //cellDateTimePicker.Checked = false; // 採用checkbox，清除值要取消勾選
        //cellDateTimePicker.Format = DateTimePickerFormat.Custom;
        //cellDateTimePicker.CustomFormat = " ";
        //cellDateTimePicker.forma
        dgvCurrent.CurrentCell.Value = " ";
    }
    cellDateTimePicker.Visible = false;
}

在 DataGridView 的 CellBeginEdit 事件內加入判斷，對應的儲存格才用DateTimePicker取代

private void dgvCertificate_CellBeginEdit(object sender, DataGridViewCellCancelEventArgs e)
{
    dgvCurrent = dgvCertificate;
    // 如果欄位是證照日期就用之前宣告的 cellDateTimePicker 取代
    // 也可以用  e.ColumnIndex == 1 判斷，用 Name 避免欄位移動又得修改
    if ("certificate_CER_DATE".Equals(dgvCertificate.Columns[e.ColumnIndex].Name))
    {
        Rectangle tempRect = dgvCertificate.GetCellDisplayRectangle(e.ColumnIndex, e.RowIndex, true);
        cellDateTimePicker.Location = tempRect.Location;
        cellDateTimePicker.Width = tempRect.Width;
        string s = dgvCurrent.CurrentCell.Value.ToString();
        cellDateTimePicker.Value = (!"".Equals(s) && !"0001/1/1 上午 12:00:00".Equals(s)) ? DateTime.Parse(s) : DateTime.Today;
        cellDateTimePicker.Checked = (!"".Equals(cellDateTimePicker.Value) && !"0001/1/1 上午 12:00:00".Equals(cellDateTimePicker.Value)) ? true : false;
        cellDateTimePicker.Visible = true; //這行要放在所有設定之後
    }
}

編輯結束後隱藏 DateTimePicker

private void dgvCertificate_CellEndEdit(object sender, DataGridViewCellEventArgs e)
{
    if ("certificate_CER_DATE".Equals(dgvCertificate.Columns[e.ColumnIndex].Name))
    {
        cellDateTimePicker.Visible = false;
    }
    //MessageBox.Show(dgvCertificate.Rows[e.RowIndex].Cells[e.ColumnIndex].Value.ToString()+
    //    dgvCertificate.Rows[e.RowIndex].Cells[e.ColumnIndex].FormattedValue.ToString());
}