如何从 DataTable 中删除空行

Question

我正在将数据从 Excel 工作表导入数据库。 Excel 工作表包含几个空行，我想删除这些空行，然后将清除的数据插入数据库。
我通过引用其他代码编写了一个代码，这是插入值的代码：

OleDbConnection cnn = new OleDbConnection(@"Provider=Microsoft.Jet.OLEDB.4.0;Data Source='" + txtExcelFile.Text + "';Extended Properties= 'Excel 8.0;HDR=Yes;IMEX=1'");
//DataTable dt = new DataTable();

try
{
    cnn.Open();
    OleDbDataAdapter data = new OleDbDataAdapter("select * from [Customers$]", cnn);
    data.Fill(dsExcel);
    dgvCustomers.ColumnHeadersVisible = false;

    SqlConnection connection = new SqlConnection("Data Source=COMPUTER-8EB749;Initial Catalog=KITS;Integrated Security=true");
    connection.Open();
    for (int i = 0; i < dsExcel.Tables[0].Rows.Count; i++)
    {
        string ID = ds.Tables[0].Rows[i][0].ToString();
        Int16 CustID = Convert.ToInt16(ID);
        string CustName = dsExcel.Tables[0].Rows[i][1].ToString();
        string CardScheme = dsExcel.Tables[0].Rows[i][2].ToString();
        string Outlet = dsExcel.Tables[0].Rows[i][3].ToString();
        string TerminalNum = dsExcel.Tables[0].Rows[i][4].ToString();
        Int32 Terminal = Convert.ToInt32(TerminalNum);
        string Date1 = dsExcel.Tables[0].Rows[i][5].ToString();
        DateTime Date = Convert.ToDateTime(Date1);
        string Time = dsExcel.Tables[0].Rows[i][6].ToString();
        DateTime DateTime = Convert.ToDateTime(Time);
        string Amount1 = ds.Tables[0].Rows[i][7].ToString();
        double Amount = Convert.ToDouble(Amount1);

        SqlCommand com = new SqlCommand("insert into Customer(CustID,CustName,CardScheme,Outlet,TerminalNum,TranDate,TranDateTime,Amount) values ('" + CustID + "','" + CustName + "','" + CardScheme + "','" + Outlet + "','" + Terminal + "','" + Date + "','" + DateTime + "','" + Amount + "')", connection);
        com.ExecuteNonQuery();
    }
    connection.Close();
}
catch (Exception ex)
{
    MessageBox.Show(ex.Message);
}
finally
{
    MessageBox.Show("Data Inserted Successfully.");
}

谁能告诉我如何删除空行以便只插入数据？！

Answer 1

您的数据库本身有空行？这很奇怪。可能会在您执行选择查询时通过说主键列不为 NULL 来过滤它

Answer 2

为什么不在插入空行之前直接忽略它们？

if(string.IsNullOrEmpty(ID + CustName + CardScheme /*.. and so on */))
{
    continue;
}

像这样：

for (int i = 0; i < dsExcel.Tables[0].Rows.Count; i++)
{
    string ID = ds.Tables[0].Rows[i][0].ToString();
    Int16 CustID = Convert.ToInt16(ID);
    string CustName = dsExcel.Tables[0].Rows[i][1].ToString();
    string CardScheme = dsExcel.Tables[0].Rows[i][2].ToString();
    string Outlet = dsExcel.Tables[0].Rows[i][3].ToString();
    string TerminalNum = dsExcel.Tables[0].Rows[i][4].ToString();
    Int32 Terminal = Convert.ToInt32(TerminalNum);
    string Date1 = dsExcel.Tables[0].Rows[i][5].ToString();
    DateTime Date = Convert.ToDateTime(Date1);
    string Time = dsExcel.Tables[0].Rows[i][6].ToString();
    DateTime DateTime = Convert.ToDateTime(Time);
    string Amount1 = ds.Tables[0].Rows[i][7].ToString();
    double Amount = Convert.ToDouble(Amount1);

    /*** Add this if-statement to you code! ***/
    if(string.IsNullOrEmpty(ID + CustName + CardScheme + Outlet + TerminalNum + Date1 + Time + Amount1))
    {
        continue;
    }

    SqlCommand com = new SqlCommand("insert into Customer(CustID,CustName,CardScheme,Outlet,TerminalNum,TranDate,TranDateTime,Amount) values ('" + CustID + "','" + CustName + "','" + CardScheme + "','" + Outlet + "','" + Terminal + "','" + Date + "','" + DateTime + "','" + Amount + "')", connection);
    com.ExecuteNonQuery();
}

Answer 3

试试这个。

public bool InsertRowsToDataBase()
{
    try
    {
        DataTable excelTable = new DataTable();

        string connString = @"Provider=Microsoft.Jet.OLEDB.4.0;Data Source='" + txtExcelFile.Text + "';Extended Properties= 'Excel 8.0;HDR=Yes;IMEX=1'";
        using (OleDbConnection cnn = new OleDbConnection(connString))
        {
            string query = "select * from [Customers$]";
            using (OleDbDataAdapter data = new OleDbDataAdapter(query, cnn))
            {
                data.Fill(excelTable);
            }
        }
        dgvCustomers.ColumnHeadersVisible = false;

        connString = "Data Source=COMPUTER-8EB749;Initial Catalog=KITS;Integrated Security=true";
        using (SqlConnection connection = new SqlConnection(connString))
        {
            connection.Open();
            for (int i = 0; i < excelTable.Rows.Length; i++)
            {
                //takes from the 3rd row
                if (i > 1)
                {
                    DataRow row = excelTable.Rows[i];
                    object ID = row[0];
                    if (ID != null && !String.IsNullOrEmpty(ID.ToString().Trim()))
                    {
                        Int16 CustID = Convert.ToInt16(ID);
                        string CustName = row[1].ToString();
                        string CardScheme = row[2].ToString();
                        string Outlet = row[3].ToString();
                        string TerminalNum = row[4].ToString();
                        Int32 Terminal = Convert.ToInt32(TerminalNum);
                        string Date1 = row[5].ToString();
                        DateTime Date = Convert.ToDateTime(Date1);
                        string Time = row[6].ToString();
                        DateTime DateTime = Convert.ToDateTime(Time);
                        string Amount1 = row[7].ToString();
                        double Amount = Convert.ToDouble(Amount1);

                        string columnNames = "CustID,CustName,CardScheme,Outlet,TerminalNum,TranDate,TranDateTime,Amount";
                        string query = String.Format("insert into Customer(0}) values ('{1}', '{2}','{3}','{4}','{5}','{6}','{7}','{8}')",
                            columnNames, CustID, CustName, CardScheme, Outlet, Terminal, Date, DateTime, Amount);
                        using (SqlCommand com = new SqlCommand(query, connection))
                        {
                            com.ExecuteNonQuery();
                        }
                    }
                }
                //this is your last row. do whatever you want with this
                DataRow lastRow = excelTable.Rows[excelTable.Rows.Count - 1];
            }
        }
        return true;
    }
    catch (Exception exception)
    {
        Elmah.ErrorSignal.FromCurrentContext().Raise(exception);
        return false;
    }
}

请注意，我只是检查 ID 是否为空，而不是插入任何这样的行，因为 ID 将是您表中的 PK。

Answer 4

try
{
    OpenOleDBConnection();
    OleDbDataAdapter dataAdapter = new OleDbDataAdapter("select * from [" + SelectedSheet + "]", Connection);

    dataAdapter.Fill(DataTable);

    if ((DataTable != null) && (DataTable.Rows != null) && (DataTable.Rows.Count > 0))
    {
        List<System.Data.DataRow> removeRowIndex = new List<System.Data.DataRow>();
        int RowCounter = 0;
        foreach (System.Data.DataRow dRow in DataTable.Rows)
        {                            
            for(int index = 0; index < DataTable.Columns.Count; index++)
            {
                if (dRow[index] == DBNull.Value)  
                {
                    removeRowIndex.Add(dRow);
                    break;
                }
                else if (string.IsNullOrEmpty(dRow[index].ToString().Trim()))
                {
                    removeRowIndex.Add(dRow);
                    break;
                }
            }
            RowCounter++;
        }
        // Remove all blank of in-valid rows
        foreach (System.Data.DataRow rowIndex in removeRowIndex)
        {
            DataTable.Rows.Remove(rowIndex);
        }
    }
}
catch(Exception e)
{
    WPFMessageBox.Show(e.Message, Globalization.GetValue("Import_ImportOption_FormHeader"), WPFMessageBoxButtons.OK, WPFMessageBoxImage.Error);
}
finally
{
    CloseOleDBConnection();
}

如果它们在任何行中有空白条目，我也会跳过这些行。

Answer 5

这将删除每列不包含任何内容或空白的所有行：

dataTable = dataTable.Rows
    .Cast<DataRow>()
    .Where(row => !row.ItemArray.All(field => field is DBNull || 
                                     string.IsNullOrWhiteSpace(field as string)))
    .CopyToDataTable();

Answer 6

我已经制作了这个可以解决问题的私有方法。 它接受一个 DataTable 作为参数并返回相同的 DataTable 而没有空行。

private DataTable StripEmptyRows(DataTable dt)
    {
        List<int> rowIndexesToBeDeleted = new List<int>();
        int indexCount = 0;
        foreach(var row in dt.Rows)
        {
            var r = (DataRow)row;
            int emptyCount = 0;
            int itemArrayCount = r.ItemArray.Length;
            foreach(var i in r.ItemArray) if(string.IsNullOrWhiteSpace (i.ToString())) emptyCount++;

            if(emptyCount == itemArrayCount) rowIndexesToBeDeleted.Add(indexCount);

            indexCount++;
        }

        int count = 0;
        foreach(var i in rowIndexesToBeDeleted)
        {
            dt.Rows.RemoveAt(i-count);
            count++;
        }

        return dt;
    }

Answer 7

public static DataTable RemoveEmptyRows(DataTable dt) 
{ 
    List removeRowIndex = new List(); 

    foreach (DataRow dRow in dt.Rows) 
    { 
        for (int index = 0; index < dt.Columns.Count; index++) 
        { 
            if (string.IsNullOrEmpty(dRow[index].ToString().Trim())) 
            { 
                removeRowIndex.Add(dRow); 
                break; 
            } 
            else if (dRow[index] == DBNull.Value) 
            { 
                removeRowIndex.Add(dRow); 
                break; 
            } 
        } 
    } 

    foreach (DataRow rowIndex in removeRowIndex) 
    { 
        dt.Rows.Remove(rowIndex); 
    } 

    return dt; 
}

Answer 8

检查空行

Foreach(DataRow as row in datable.Rows) {
    var isEmpty = row.ItemArray.All(c => c is DBNull);
    if(!isEmpty) {
        //Your Logic
    }
}

Answer 9

这非常适合我：

dt.Load(cmd.ExecuteReader());
var x = dt.Rows.Cast<DataRow>()
   .Where(row => !Array.TrueForAll(row.ItemArray, value => 
   { return value.ToString().Length == 0; }
   ));

dt = x.CopyToDataTable();

Answer 10

我修改了 Cfrim 的答案。您需要检查空字符串和空白字符串。空白来自已删除的单元格，空白来自已删除的数据。

private DataTable StripEmptyRows(DataTable dt)
        {
            List<int> rowIndexesToBeDeleted = new List<int>();
            int indexCount = 0;
            foreach(var row in dt.Rows)
            {
                var r = (DataRow)row;
                int emptyCount = 0;
                int itemArrayCount = r.ItemArray.Length;
                    foreach (var i in dr.ItemArray)
                    {
                        if (string.IsNullOrEmpty(i.ToString()) || string.IsNullOrWhiteSpace(i.ToString()))
                            emptyCount++;
                    }

                if(emptyCount == itemArrayCount) rowIndexesToBeDeleted.Add(indexCount);

                indexCount++;
            }

            int count = 0;
            foreach(var i in rowIndexesToBeDeleted)
            {
                dt.Rows.RemoveAt(i-count);
                count++;
            }

            return dt;
        }

Answer 11

我在@Levitikon 帖子https://stackoverflow.com/a/9233696/5848472 中稍作改动 使用@shA.t 注释，此代码删除数据表中的所有空行和列：

dt = ds.Tables[tablename].Rows
    .Cast<DataRow>()
    .Where(row => !row.ItemArray.All(field => field is DBNull || 
           string.IsNullOrWhiteSpace(field as string ?? field.ToString())))
    .CopyToDataTable();
foreach (var column in dt.Columns.Cast<DataColumn>().ToArray())
    {
        if (dt.AsEnumerable().All(dr => dr.IsNull(column)))
            dt.Columns.Remove(column);
    }

Answer 12

这将从数据表中删除所有空行：

DataTable dt = dt.Rows
                 .Cast<DataRow>()
                 .Where(row => !row.ItemArray.All(f => f is DBNull))
                 .CopyToDataTable();

或

DataTable dt = dt.Rows
                 .Cast<DataRow>()
                 .Where(row => !row.ItemArray.All(f => f is DBNull || 
                                  string.IsNullOrEmpty(f as string ?? f.ToString())))
                 .CopyToDataTable();

Answer 13

这对我有用。如果我们不检查行，直接做CopyToDataTable()，那么当数据表有空行时，你可能会得到一个异常。

var rows = tbl.Rows.Cast<DataRow>()
                            .Where(row => !row.ItemArray.All(field => field is DBNull || String.IsNullOrWhiteSpace(field as string ?? field.ToString())));

if (rows.Any())
    tbl = rows.CopyToDataTable();

Answer 14

基于我使用的现有答案

public static bool AllColumnsEmpty(this DataRow row)
{
    if (row == null)
    {
        return true;
    }
    else
    {
        foreach (var value in row.ItemArray)
        {
            if (value != null && value.ToString() != "")
            {
                return false;
            }
        }
        return true;
    }
}

public static void RemoveEmptyRows(this DataTable data)
{
    var rowsToDelete = data.Rows.Cast<DataRow>()
        .Where(row => row.AllColumnsEmpty())
        .ToList();

    rowsToDelete.ForEach(row => data.Rows.Remove(row));
}

然后使用

someDatatable.RemoveEmptyRows();

Answer 15

for (int i = dt.Rows.Count - 1; i >= 0; i--) {
    if (dt.Rows[i][1] == DBNull.Value) {
        dt.Rows[i].Delete();
    }
}
dt.AcceptChanges();
return dt;