以下は、区切りファイルを読み取り、文字列を切り捨てない DataTable (すべての文字列) を返す単純なクラスです。列名がファイルにない場合に列名を指定するためのオーバーロードされたメソッドがあります。多分あなたはそれを使うことができますか？
インポートされた名前空間
using System;
using System.Text;
using System.Data;
using System.IO;
コード
/// <summary>
/// Simple class for reading delimited text files
/// </summary>
public class DelimitedTextReader
{
/// <summary>
/// Read the file and return a DataTable
/// </summary>
/// <param name="filename">File to read</param>
/// <param name="delimiter">Delimiting string</param>
/// <returns>Populated DataTable</returns>
public static DataTable ReadFile(string filename, string delimiter)
{
return ReadFile(filename, delimiter, null);
}
/// <summary>
/// Read the file and return a DataTable
/// </summary>
/// <param name="filename">File to read</param>
/// <param name="delimiter">Delimiting string</param>
/// <param name="columnNames">Array of column names</param>
/// <returns>Populated DataTable</returns>
public static DataTable ReadFile(string filename, string delimiter, string[] columnNames)
{
// Create the new table
DataTable data = new DataTable();
data.Locale = System.Globalization.CultureInfo.CurrentCulture;
// Check file
if (!File.Exists(filename))
throw new FileNotFoundException("File not found", filename);
// Process the file line by line
string line;
using (TextReader tr = new StreamReader(filename, Encoding.Default))
{
// If column names were not passed, we'll read them from the file
if (columnNames == null)
{
// Get the first line
line = tr.ReadLine();
if (string.IsNullOrEmpty(line))
throw new IOException("Could not read column names from file.");
columnNames = line.Split(new string[] { delimiter }, StringSplitOptions.RemoveEmptyEntries);
}
// Add the columns to the data table
foreach (string colName in columnNames)
data.Columns.Add(colName);
// Read the file
string[] columns;
while ((line = tr.ReadLine()) != null)
{
columns = line.Split(new string[] { delimiter }, StringSplitOptions.None);
// Ensure we have the same number of columns
if (columns.Length != columnNames.Length)
{
string message = "Data row has {0} columns and {1} are defined by column names.";
throw new DataException(string.Format(message, columns.Length, columnNames.Length));
}
data.Rows.Add(columns);
}
}
return data;
}
}
必要な名前空間
using System;
using System.Data;
using System.Windows.Forms;
using System.Data.SqlClient;
using System.Diagnostics;
これを呼び出して SQL データベースにアップロードする例を次に示します。
Stopwatch sw = new Stopwatch();
TimeSpan tsRead;
TimeSpan tsTrunc;
TimeSpan tsBcp;
int rows;
sw.Start();
using (DataTable dt = DelimitedTextReader.ReadFile(textBox1.Text, "\t"))
{
tsRead = sw.Elapsed;
sw.Reset();
rows = dt.Rows.Count;
string connect = @"Data Source=.;Initial Catalog=MyDB;Integrated Security=SSPI";
using (SqlConnection cn = new SqlConnection(connect))
using (SqlCommand cmd = new SqlCommand("TRUNCATE TABLE dbo.UploadTable", cn))
using (SqlBulkCopy bcp = new SqlBulkCopy(cn))
{
cn.Open();
sw.Start();
cmd.ExecuteNonQuery();
tsTrunc = sw.Elapsed;
sw.Reset();
sw.Start();
bcp.DestinationTableName = "dbo.UploadTable";
bcp.ColumnMappings.Add("Column A", "ColumnA");
bcp.ColumnMappings.Add("Column D", "ColumnD");
bcp.WriteToServer(dt);
tsBcp = sw.Elapsed;
sw.Reset();
}
}
string message = "File read:\t{0}\r\nTruncate:\t{1}\r\nBcp:\t{2}\r\n\r\nTotal time:\t{3}\r\nTotal rows:\t{4}";
MessageBox.Show(string.Format(message, tsRead, tsTrunc, tsBcp, tsRead + tsTrunc + tsBcp, rows));