Question

如何把DataSet中的数据写入CSV文件？

Answer 1

不知道你用的是什么开发环境，你也没有说，如果是.net的话用下面这段程序吧：
using System;
using System.Collections.Generic;
using System.Text;
using System.Data;
using System.Data.Common;
using System.Data.OleDb;
using System.Windows.Forms;
using System.IO;
namespace XRSoft.Client.Common
{

/// <summary>
/// 将DataSet写成CSV文件
/// </summary>
public class DataSet2CSV
{
#region 001----将DataSet转换成CSV文件
public static void Export2CSV(DataSet ds, string tableName, bool containColumName, string fileName)
{
string csvStr = ConverDataSet2CSV(ds,tableName,containColumName);
if(csvStr=="") return;
FileStream fs = new FileStream(fileName, FileMode.Create, FileAccess.ReadWrite);
//将string转换成byte[]
byte[] csvArray = System.Text.Encoding.ASCII.GetBytes(csvStr.ToCharArray(), 0, csvStr.Length - 1);
fs.Write(csvArray,0,csvStr.Length - 1);
fs.Close();
fs = null;
}
// <summary>
//将指定的数据集中指定的表转换成CSV字符串
// </summary>
// <param name="ds"></param>
// <param name="tableName"></param>
// <returns></returns>
private static string ConverDataSet2CSV(DataSet ds, string tableName,bool containColumName)
{
//首先判断数据集中是否包含指定的表
if (ds == null || !ds.Tables.Contains(tableName))
{
MessageBox.Show("指定的数据集为空或不包含要写出的数据表！", "系统提示：", MessageBoxButtons.OK, MessageBoxIcon.Stop);
return "";
}
string csvStr = "";
//下面写出数据
DataTable tb = ds.Tables[tableName];
//写表名
//csvStr += tb.TableName + "\n";
//第一步：写出列名
if (containColumName)
{
foreach (DataColumn column in tb.Columns)
{
csvStr += "\""+column.ColumnName +"\"" +",";
}
//去掉最后一个","
csvStr = csvStr.Remove(csvStr.LastIndexOf(","), 1);
csvStr += "\n";
}
//第二步：写出数据
foreach (DataRow row in tb.Rows)
{
foreach (DataColumn column in tb.Columns)
{
csvStr += "\"" + row[column].ToString() + "\"" + ",";
}
csvStr = csvStr.Remove(csvStr.LastIndexOf(","), 1);
csvStr += "\n";
}
return csvStr;
}

#endregion

#region 002----从CSV文件填充DataSet

public static DataSet ConverCSV2DataSet(string fileName, string tableName)
{
DataSet ds = new DataSet();
string _filePath, _fileName;
_filePath = fileName.Substring(0, fileName.LastIndexOf(@"\") + 1);
_fileName = fileName.Substring(fileName.LastIndexOf(@"\")+1);
string conStr = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source= " + _filePath + @"\" + ";Extended Properties=\"Text;HDR=Yes;FMT=Delimited\"";
OleDbConnection oleCon = new OleDbConnection(conStr);
OleDbDataAdapter da = new OleDbDataAdapter("Select * from " + _fileName,oleCon);
da.Fill(ds,tableName);
oleCon.Close();
return ds;
}
#endregion

}
}