Question

我有2张桌子.. 我想检查具有数据库值的数据集中的Excel工作表值：怎么检查??

这是代码：

lblmsg.Text = "";
    try
    {
        //System.Threading.Thread.Sleep(5000);
        int  stateid = 0, cityid = 0;
        DataTable dtbank = new DataTable();
        DataSet ds = new DataSet();
        if (fildetails.HasFile)
        {
            string fileExtension = System.IO.Path.GetExtension(fildetails.FileName);

            if (fileExtension == ".xls" || fileExtension == ".xlsx")
            {
                string fileLocation = Server.MapPath("/NewFolder1/") + fildetails.FileName;

                if (System.IO.File.Exists(fileLocation))
                {

                    // System.IO.File.Delete(fileLocation);
                }
                fildetails.SaveAs(fileLocation);
                string excelConnectionString = string.Empty;
                excelConnectionString = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source=" +
                fileLocation + ";Extended Properties=\"Excel 12.0;HDR=Yes;IMEX=2\"";
                //connection String for xls file format.
                if (fileExtension == ".xls")
                {
                    excelConnectionString = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" +
                    fileLocation + ";Extended Properties=\"Excel 8.0;HDR=Yes;IMEX=2\"";
                }
                //connection String for xlsx file format.
                else if (fileExtension == ".xlsx")
                {
                    excelConnectionString = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source=" +
                    fileLocation + ";Extended Properties=\"Excel 12.0;HDR=Yes;IMEX=2\"";
                }
                //Create Connection to Excel work book and add oledb namespace
                OleDbConnection excelConnection = new OleDbConnection(excelConnectionString);
                excelConnection.Open();
                DataTable dt = new DataTable();

                dt = excelConnection.GetOleDbSchemaTable(OleDbSchemaGuid.Tables, null);
                if (dt == null)
                {
                    return;
                }

                String[] excelSheets = new String[dt.Rows.Count];
                int t = 0;
                //excel data saves in temp file here.
                foreach (DataRow row in dt.Rows)
                {
                    string x = row["TABLE_NAME"].ToString();
                    if (x != "Sheet1$_" && x != "Sheet2$_" && x != "Sheet3$_" && x != "Sheet4$_" && x != "Sheet5$_")
                    {
                        excelSheets[t] = row["TABLE_NAME"].ToString();
                        t++;
                    }
                }
                OleDbConnection excelConnection1 = new OleDbConnection(excelConnectionString);

                int totalsheet = excelSheets.Length;
                for (int i = 0; i < totalsheet; i++)
                {
                    string query = string.Format("Select * from [{0}]", excelSheets[i]);
                    using (OleDbDataAdapter dataAdapter = new OleDbDataAdapter(query, excelConnection1))
                    {
                        dataAdapter.Fill(ds);
                    }
                }
            }
            if (fileExtension.ToString().ToLower().Equals(".xml"))
            {
                string fileLocation = Server.MapPath("~/Content/") + Request.Files["FileUpload"].FileName;
                if (System.IO.File.Exists(fileLocation))
                {
                    System.IO.File.Delete(fileLocation);
                }

                Request.Files["FileUpload"].SaveAs(fileLocation);
                XmlTextReader xmlreader = new XmlTextReader(fileLocation);
                // DataSet ds = new DataSet();
                ds.ReadXml(xmlreader);
                xmlreader.Close();
            }

这里我在ds中获得excel值。我该怎么办？怎么检查？我试过这件事：

  BL objbankbl=new BL();
                for (int j = 0; j < ds.Tables.Count; j++)
                {
                    for (int i = 0; i < ds.Tables[j].Rows.Count; i++)
                    {
                        ////city_name///
                        if (!DBNull.Value.Equals(ds.Tables[j].Rows[i][0]))
                        {
                           // dtbank = objbankbl.GetReportDate("","","", ds.Tables[j].Rows[i][0].ToString(), "", "", "","","");
                            dtbank = objbankbl.GetReportDate(ds.Tables[j].Rows[i][0].ToString());


                            if (dtbank.Rows.Count > 0 && ( ds.Tables[j].Rows[i][0].ToString() == dtbank.Rows[j]["Name"]) )
                            {
                                stateid = Convert.ToInt32(dtbank.Rows[0]["ID"]);
                            }
                            else
                            {
                                string bankname = ds.Tables[j].Rows[i][0].ToString();
                                if (bankname != " " || bankname != null)
                                {
                                    //stateid = objbankbl.Insert(1, ds.Tables[j].Rows[i][0].ToString(), "", "", 0, "", 0);
                                }
                            }
                        }

Answer 1

DataTable dt = new DataTable();
dt.Columns.Add();
dt.Columns.Add();
dt.Columns.Add();
dt.Rows.Add(1, "Test1", "Sample1");
dt.Rows.Add(2, "Test2", "Sample2");
dt.Rows.Add(3, "Test3", "Sample3");
dt.Rows.Add(4, "Test4", "Sample4");
dt.Rows.Add(5, "Test5", "Sample5");

var duplicates = dt.AsEnumerable().GroupBy(r => r[0]).Where(gr => gr.Count() > 1).ToList();
Console.WriteLine("Duplicate found: {0}", duplicates.Any());

dt.Rows.Add(1, "Test6", "Sample6");  // Duplicate on 1
dt.Rows.Add(1, "Test6", "Sample6");  // Duplicate on 1
dt.Rows.Add(3, "Test6", "Sample6");  // Duplicate on 3
dt.Rows.Add(5, "Test6", "Sample6");  // Duplicate on 5

duplicates = dt.AsEnumerable().GroupBy(r => r[0]).Where(gr => gr.Count() > 1).ToList();
if (duplicates.Any())
    Console.WriteLine("Duplicate found for Classes: {0}", String.Join(", ", duplicates.Select(dupl => dupl.Key)));

Console.ReadLine();

我希望这个例子可以帮助你。

Answer 2

使用DataView.ToTable方法可以轻松处理。语法如下。

DataView.ToTable(bool distinct, string[] columnNames)

distinct：如果是，则返回的DataTable包含对第二个参数中指定的所有列具有不同值的行。默认值为false。

columnNames：一个字符串数组，其中包含要包含在返回表中的列名列表。返回表中列的顺序与数组中显示的列相同。

<强>练习1

DataTable temp = dt.DefaultView.ToTable(true, "Region");

<强>练习2

DataTable temp = dt.DefaultView.ToTable(true, "Region", "City");

Answer 3

有几种方法可以使它工作，我想到的前两种方法是使用HashTables或LinQ表达式。

看看这个：从数据表中删除重复条目的最佳方法，但不是删除副本（查看第二个foreach），而是打印消息。

    public void CheckDuplicateRows(DataTable dTable, string colName)
{
   Hashtable hTable = new Hashtable();
   ArrayList duplicateList = new ArrayList();

   //Add list of all the unique item value to hashtable, which stores combination of     key, value pair.
   //And add duplicate item value in arraylist.
   foreach (DataRow drow in dTable.Rows)
   {
      if (hTable.Contains(drow[colName]))
         duplicateList.Add(drow);
      else
         hTable.Add(drow[colName], string.Empty); 
   }

  //Checks the list dimension to verify if there is any duplicate
  if(duplicateList.Count() > 0)
  {
  //you can print your message here or eventually get info about the duplicate row
  }   
}

上传到sql时excel重复检查

3 个答案: