Question

我在DataTable中有以下值

Affiliate Name | Call
---------------|-----
A              |   2
B              |   1  
B              |   0
A              |   3

如何针对Call＆＃39; A＆＃39;检索Affiliate Name的总计数。在上面的示例中，它应该返回5.

foreach (DataRow row in dt.Rows)
{
    string CallsOffered = //Get count
}

Answer 1

您可以使用DataTable.Compute方法

var sumOfA = dt.Compute("Sum(Call)", "[Affiliate Name] = 'A'");

或使用LINQ

var sumOfA = dt.AsEnumerable()
               .Where(dr => dr.Field<string>("Affiliate Name").Equals("A"))
               .Sum(dr => dr.Field<int>("Call"));

如果你想获得所有Affiliate Name值的调用总和，请使用匿名类型的LINQ

var results = dt.AsEnumerable()
                .GroupBy(dr => dr.Field<string>("Affiliate Name"))
                .Select((group, dr) => new 
                {
                    AffiliateName = group.Key,
                   CallsCount = group.Sum(dr.Field<int>("Call")))
                });

foreach(var result in results)
{
    // Use results
    Console.WriteLine($"{result.AffiliateName}: {result.CallsCount}");
}

Answer 2

您可以使用

    int CallsOffered=0;
    foreach (DataRow row in dt.Rows)
    {
      if(row["Affiliate_Name"].ToString()=="A")
        CallsOffered += int.Parse(row["Call"].ToString());
    }

Answer 3

只需使用

object sumObject = table.Compute("Sum(Call)", "Affiliate_Name = 'A'");

Answer 4

// with this code you can use linq features in all other steps
// add each column you need them to use them with linq  
var records = dt.AsEnumerable().Select(row =>
new
{
    Affiliate = row.Field<string>("Affiliate(col name)"),
    Call = Convert.ToInt32(row.Field<int>("Call(col name)"))
});
int count = records.Where(q => q.Affiliate == "A").Sum(q => q.Call);

获取DataTable列的SUM

4 个答案: