Question

我正在尝试将日期解析为SQL，但是该命令似乎忽略了参数：

private void updateTasksDGV(DateTime? start, DateTime? end)
    {
        if (start == null)
        {
            string query = "select * from CRS_Diary where cast(EndDate as date) <= convert(date,GETDATE()) and Complete = 0";
            dgvTasks.DataSource = GetTable(query);
            return;
        }

        try
        {
            using (SqlConnection connection = getSQlCon())

            {

                using (SqlCommand cmd = new SqlCommand(@"Select * from crs_diary where enddate between @Start and @End and complete = 0", connection))
                {
                    MessageBox.Show("made it to conn " + start.ToString() + "  -  " + end.ToString());
                    cmd.CommandType = CommandType.Text;

                    SqlParameter parameter = new SqlParameter();
                    parameter.ParameterName = "@Start";
                    parameter.SqlDbType = SqlDbType.DateTime;
                    parameter.Direction = ParameterDirection.Input;
                    parameter.Value = start;

                    SqlParameter parameter2 = new SqlParameter();
                    parameter2.ParameterName = "@End";
                    parameter2.SqlDbType = SqlDbType.DateTime;
                    parameter2.Direction = ParameterDirection.Input;
                    parameter2.Value = end;



                    cmd.Parameters.Add(parameter);
                    cmd.Parameters.Add(parameter2);

                    //cmd.Parameters.AddWithValue("@Start", SqlDbType.DateTime).Value = start.Value;
                    //cmd.Parameters.AddWithValue("@End", SqlDbType.DateTime).Value = end.Value;

                    connection.Open();
                    cmd.ExecuteNonQuery();

                    System.Windows.Forms.Clipboard.SetText(cmd.CommandText.ToString());

                }
            }
        }
        catch (System.Data.DataException ex)
        {
            MessageBox.Show(ex.Message);

        }

    }

我可以使它使用commandtype存储过程传递参数，但是在这种情况下，我不希望这样做。输出/ DGV没有执行任何操作。

Answer 1

您应该使用ExecuteReader而不是ExecuteNonQuery。还要注意，对于SQL Server，您不应将BETWEEN用于日期范围，而应使用> =和<。稍微修改了代码：

private void updateTasksDGV(DateTime? start, DateTime? end)
{
    if (!end.HasValue)
    {
      end = DateTime.MaxValue;
    }
    if (!start.HasValue)
    {
        string query = "select * 
            from CRS_Diary 
            where EndDate <= GETDATE() and Complete = 0";
        dgvTasks.DataSource = GetTable(query);
        return;
    }

    try
    {
        DataTable tbl = new DataTable();
        using (SqlConnection connection = getSQlCon())

        {

            using (SqlCommand cmd = new SqlCommand(@"Select * from crs_diary 
            where enddate >= @Start and endDate < @End and complete = 0", connection))
            {
                MessageBox.Show("made it to conn " + start.ToString() + "  -  " + end.ToString());

                cmd.Parameters.Add(new SqlParameter("@Start", SqlDbType.DateTime));
                cmd.Parameters.Add(new SqlParameter("@End", SqlDbType.DateTime));

                cmd.Parameters["@Start"].Value = start;
                cmd.Parameters["@End"].Value = end;

                connection.Open();
                tbl.Load(cmd.ExecuteReader());

                System.Windows.Forms.Clipboard.SetText(cmd.CommandText.ToString());
            }
        }
        dgvTasks.DataSource = null;
        dgvTasks.DataSource = tbl;
    }
    catch (System.Data.DataException ex)
    {
        MessageBox.Show(ex.Message);

    }
}

请注意，如果您要查询2018年7月的数据，则开始日期为：2018/7/1，结束日期为2018/8/1（排除的最短日期时间）。

不在存储过程中时将日期解析为SQL

1 个答案: