c# 导入、导出csv文件、excel文件、xml文件和txt文件
为了方便操作常用文件，特归纳总结。
一、先贴出处理XML文件代码：
public class DealXML { /// <summary> /// 将xml对象内容转换为dataset /// </summary> /// <param name="xmlData"></param> /// <returns></returns> private static DataSet ConvertXMLToDataSet(string xmlData) { using (StringReader stream = new StringReader(xmlData)) { using (XmlTextReader reader = new XmlTextReader(stream)) { try { DataSet xmlDS = new DataSet(); xmlDS.ReadXml(reader); return xmlDS; } catch (Exception ex) { throw ex; } finally { if (reader != null) reader.Close(); } } } } /// <summary> /// 将DataSet转换为xml对象字符串 /// </summary> /// <param name="xmlDS"></param> /// <returns></returns> public static string ConvertDataSetToXML(DataSet xmlDS) { using (MemoryStream stream = new MemoryStream()) { //从stream装载到XmlTextReader using (XmlTextWriter writer = new XmlTextWriter(stream, Encoding.Default)) { try { //用WriteXml方法写入文件. xmlDS.WriteXml(writer); int count = (int)stream.Length; byte[] arr = new byte[count]; stream.Seek(0, SeekOrigin.Begin); stream.Read(arr, 0, count); return Encoding.Default.GetString(arr).Trim(); } catch (System.Exception ex) { throw ex; } finally { if (writer != null) writer.Close(); } } } } /// <summary> /// 将DataSet转换为xml文件 /// </summary> /// <param name="xmlDS"></param> /// <param name="xmlFile"></param> public static void ConvertDataSetToXMLFile(DataSet xmlDS,string xmlFile) { using (MemoryStream stream = new MemoryStream()) { //从stream装载到XmlTextReader using (XmlTextWriter writer = new XmlTextWriter(stream, Encoding.Default)) { try { //用WriteXml方法写入文件. xmlDS.WriteXml(writer); int count = (int)stream.Length; byte[] arr = new byte[count]; stream.Seek(0, SeekOrigin.Begin); stream.Read(arr, 0, count); //返回Encoding.Default编码的文本 using (StreamWriter sw = new StreamWriter(xmlFile)) { sw.WriteLine("<?xml version=\"1.0\" encoding=\"utf-8\" ?>"); string ss = System.Text.Encoding.Default.GetString(arr).Trim(); sw.WriteLine(ss); sw.Flush(); sw.Close(); } //重新排版生成的xml文档 XmlDocument doc = new XmlDocument(); doc.Load(xmlFile); doc.Save(xmlFile); doc = null; } catch (System.Exception ex) { throw ex; } finally { if (writer != null) writer.Close(); } } } } // Xml结构的文件读到DataSet中 public static DataSet XmlToDataTableByFile(string fileName) { XmlDocument doc = new XmlDocument(); doc.Load(fileName); string xmlString = doc.InnerXml; DataSet XmlDS = ConvertXMLToDataSet(xmlString); return XmlDS; } }
二、操作csv文件：
public class CSVFileHelper { /// <summary> /// 将DataTable中数据写入到CSV文件中 /// </summary> /// <param name="dt">提供保存数据的DataTable</param> /// <param name="fileName">CSV的文件路径</param> public static bool SaveCSV(DataTable dt, string fullPath) { FileInfo fi = new FileInfo(fullPath); if (!fi.Directory.Exists) { fi.Directory.Create(); } using (FileStream fs = new FileStream(fullPath, System.IO.FileMode.Create, System.IO.FileAccess.Write)) { //StreamWriter sw = new StreamWriter(fs, System.Text.Encoding.Default); using (StreamWriter sw = new StreamWriter(fs, System.Text.Encoding.UTF8)) { try { string data = ""; //写出列名称 for (int i = 0; i < dt.Columns.Count; i++) { data += dt.Columns[i].ColumnName.ToString(); if (i < dt.Columns.Count - 1) { data += ","; } } sw.WriteLine(data); //写出各行数据 for (int i = 0; i < dt.Rows.Count; i++) { data = ""; for (int j = 0; j < dt.Columns.Count; j++) { string str = dt.Rows[i][j].ToString(); str = str.Replace("\"", "\"\"");//替换英文冒号 英文冒号需要换成两个冒号 if (str.Contains(',') || str.Contains('"') || str.Contains('\r') || str.Contains('\n')) //含逗号 冒号 换行符的需要放到引号中 { str = string.Format("\"{0}\"", str); } data += str; if (j < dt.Columns.Count - 1) { data += ","; } } sw.WriteLine(data); } } catch (Exception) { return false; } finally { sw.Close(); fs.Close(); } return true; } } } /// <summary> /// 将CSV文件的数据读取到DataTable中 /// </summary> /// <param name="fileName">CSV文件路径</param> /// <returns>返回读取了CSV数据的DataTable</returns> public static DataTable OpenCSV(string filePath) { //Encoding encoding = Common.GetType(filePath); //Encoding.ASCII;// DataTable dt = new DataTable(); using (FileStream fs = new FileStream(filePath, System.IO.FileMode.Open, System.IO.FileAccess.Read)) { using (StreamReader sr = new StreamReader(fs, Encoding.UTF8)) { //StreamReader sr = new StreamReader(fs, encoding); //string fileContent = sr.ReadToEnd(); //encoding = sr.CurrentEncoding; //记录每次读取的一行记录 string strLine = ""; //记录每行记录中的各字段内容 string[] aryLine = null; string[] tableHead = null; //标示列数 int columnCount = 0; //标示是否是读取的第一行 bool IsFirst = true; //逐行读取CSV中的数据 while ((strLine = sr.ReadLine()) != null) { //strLine = Common.ConvertStringUTF8(strLine, encoding); //strLine = Common.ConvertStringUTF8(strLine); if (IsFirst == true) { tableHead = strLine.Split(','); IsFirst = false; columnCount = tableHead.Length; //创建列 for (int i = 0; i < columnCount; i++) { DataColumn dc = new DataColumn(tableHead[i]); dt.Columns.Add(dc); } } else { aryLine = strLine.Split(','); DataRow dr = dt.NewRow(); for (int j = 0; j < columnCount; j++) { dr[j] = aryLine[j]; } dt.Rows.Add(dr); } } if (aryLine != null && aryLine.Length > 0) { dt.DefaultView.Sort = tableHead[0] + " " + "asc"; } sr.Close(); fs.Close(); } } return dt; } }
三、操作Excel文件，目前支持导入.xls文件：
public class DealXLS { public static DataSet ExcelToDS(string Path) { if (Path.Length <= 0) { return null; } string strConn = ""; string tableName = ""; if (Path.Substring(Path.Length - 1, 1) == "s") strConn = "Provider=Microsoft.Jet.OLEDB.4.0;" + "Data Source=" + Path + ";" + "Extended Properties=Excel 8.0;"; else if (Path.Substring(Path.Length - 1, 1) == "x") { throw new Exception("仅支持.xls版本导入"); } OleDbConnection conn = new OleDbConnection(strConn); conn.Open(); string strExcel = ""; OleDbDataAdapter myCommand = null; DataSet ds = new DataSet(); ; DataTable schemaTable = conn.GetOleDbSchemaTable(System.Data.OleDb.OleDbSchemaGuid.Tables, null); for (int i = 0; i < schemaTable.Rows.Count; i++) { tableName = schemaTable.Rows[i][2].ToString().Trim(); if (!tableName.Contains("FilterDatabase") && tableName.Substring(tableName.Length - 1, 1) != "_") { ds.Tables.Add(tableName); strExcel = string.Format("select * from [{0}]", tableName); myCommand = new OleDbDataAdapter(strExcel, strConn); myCommand.Fill(ds, tableName); } } conn.Close(); return ds; } }
网上有好多利用第三方dll来操作Excel文件，提供下列网址：http://www.cnblogs.com/lazyneal/p/6148912.html、http://www.cnblogs.com/xiaolifeidao/p/3651940.html
四、.txt文件，有好多方法：
//读取 public void Read(string path) { StreamReader sr = new StreamReader(path,Encoding.Default); String line; while ((line = sr.ReadLine()) != null) { Console.WriteLine(line.ToString()); } } //写入 public static bool SaveTxt(string filePath, params string[] arrLog) { using (StreamWriter sw = new StreamWriter(filePath, false)) { try { for (int i = 0; i < arrLog.Length; i++) { sw.WriteLine(arrLog[i]); } } catch (Exception) { return false; } sw.Close(); return true; } }
