如何使用dataview检查相同的值

Question

DataTable dt = new DataTable();
res.Fill(dt);

它是get sql数据代码。

DataRow dr = dt.NewRow();
dr[0] = tt_id;
dr[1] = fault_desc;
dr[2] = tt_time;

dt.Rows.Add(dr);

DataView dv = new DataView(dt);

Response.Write(dv);

if (dv.Count != dv.ToTable(true, "tt_id").Rows.Count) {
  // string sqlstr = string.Format("insert 
}

我想使用dataview来检查以前在sql中存在的新数据，如果存在，取消插入。问题是，反应说，我有相同的价值，但我检查它的地方没有任何相同的值在dv。这里面怎么了？

Answer 1

var duplicateValues = (from row in dt.AsEnumerable()
                   orderby row.Field<string>("Id")
                   select new DuplicateObject
                   {
                       Id = row.Field<string>("Id"),
                       Name = row.Field<string>("Name"),
                       Skill = row.Field<string>("Skill")
                   }).Distinct(new DuplicateObjectComparer()).ToList();

string dupValue = string.Empty;

foreach (var dup in duplicateValues)
{
dupValue = dup.Id + " - " + dup.Name + " - " + dup.Skill;
Console.WriteLine("Duplicate entry:" + dupValue);
}

if (duplicateValues.Count == 0)
Console.WriteLine("No duplicate entry");
// Supporting classes
// Gives a strongly type class from the Linq query    
public class DuplicateObject
{
  public string Id { get; set; }
  public string Name { get; set; }
  public string Skill { get; set; }
}