如何在相同日期的行末尾添加相同日期的 DataGridView 行的总和作为新的“总计”行？

Question

我有一个 DataGridView 来显示来自 DataTable“dtGrid”的数据。 dtGrid 有“MyDate”和“Amount”两列，行是这样的，

dtGrid.Rows.Add(new object[] { "2020-09-14", 100 });
dtGrid.Rows.Add(new object[] { "2020-09-14", 150 });
dtGrid.Rows.Add(new object[] { "2020-09-14", 110 });
dtGrid.Rows.Add(new object[] { "2020-09-16", 200 });
dtGrid.Rows.Add(new object[] { "2020-09-16", 170 });

现在，我需要将 DataGridView 填充为

2020-09-14 |100
2020-09-14 |150
2020-09-14 |110
Total|360
2020-09-16 |200
2020-09-16 |170
Total|370

我试图在循环中检查 dtGrid 的下一行日期，例如，

for (int i = 0; i < dtGrid.Rows.Count; i++)
        {
            if (i + 1 < dtGrid.Rows.Count && dtGrid.Rows[i][0] != dtGrid.Rows[i + 1][0])
            {
                GridReport.Rows.Add(dtGrid.Rows[i][0], dtGrid.Rows[i][1]);
                var dtFiltered = dtGrid.AsEnumerable()
                        .Where(x => x.Field<DateTime>("MyDate").ToString().Equals(dtGrid.Rows[i][0].ToString()))
                        .CopyToDataTable();
                var Total = dtFiltered.AsEnumerable()
                         .Sum(x => x.Field<double>("Amount"));

                GridReport.Rows.Add("Total:", Total);
            }
            else if(i + 1 < dtGrid.Rows.Count && dtGrid.Rows[i][0] == dtGrid.Rows[i + 1][0])
            {
                GridReport.Rows.Add(dtGrid.Rows[i][0], dtGrid.Rows[i][1]);
            }
            else if (i + 1 == dtGrid.Rows.Count)
            {
                GridReport.Rows.Add(dtGrid.Rows[i][0], dtGrid.Rows[i][1]);
                var dtFiltered = dtGrid.AsEnumerable()
                        .Where(x => x.Field<DateTime>("MyDate").ToString().Equals(dtGrid.Rows[i][0].ToString()))
                        .CopyToDataTable();
                var Total = dtFiltered.AsEnumerable()
                         .Sum(x => x.Field<double>("Amount"));

                GridReport.Rows.Add("Total:", Total);
            }
        }

它只是不起作用。任何建议将不胜感激。

Answer 1

尝试以下解决方案

dtGrid = new DataTable();
dtGrid.Columns.Add("MyDate", typeof(string));
dtGrid.Columns.Add("Amount", typeof(decimal));

dtGrid.Rows.Add(new object[] { "2020-09-14", 100 });
dtGrid.Rows.Add(new object[] { "2020-09-14", 150 });
dtGrid.Rows.Add(new object[] { "2020-09-14", 110 });
dtGrid.Rows.Add(new object[] { "2020-09-16", 200 });
dtGrid.Rows.Add(new object[] { "2020-09-16", 170 });

var rows = dtGrid.AsEnumerable()
    .GroupBy(row => row.Field<string>("MyDate"), row => row.Field<decimal>("Amount"))
    .Select(g => new { Date = g.Key, Amounts = string.Join(", ", g), Total = g.Sum() });

var dt = new DataTable();
dt.Columns.Add("Date", typeof(string));
dt.Columns.Add("Amounts", typeof(string));
dt.Columns.Add("Total", typeof(decimal));

foreach (var row in rows)
    dt.Rows.Add(row.Date, row.Amounts, row.Total);

GridReport.DataSource = dt;

它会给出以下结果

Date       | Amounts       | Total
2020-09-14 | 100, 150, 110 | 360
2020-04-16 | 200, 170      | 370

Answer 2

试试这个，创建您创建的逻辑的简短版本

var total = 0;
for (var i = 0; i < dtGrid.Rows.Count; i++)
{
   if (i == 0)
   {
      //Cells[1] will get amount
      total = Convert.ToInt32(dtGrid.Rows[i].Cells[1].Value);
   } //Cells[0] will get date
   else if (dtGrid.Rows[i - 1].Cells[0].Value == dtGrid.Rows[i].Cells[0].Value)
   {
      total = total + Convert.ToInt32(dtGrid.Rows[i].Cells[1].Value);
   }
   else
   {
      dtGrid.Rows.Insert(i, "Total : ", total);
      //resets total value
      total = 0;
      //will add index position where total is inserted
      i = i + 1;
   }
}