1、FileStream只处理原始字节，不处理字符，使用StreamRead和StreamWrite处理字符。
1）使用FileStream处理字符串时，须经过中间类的转换：
byte[] byData = new byte[200]; char[] charData = new Char[200]; //Byte2Char Decoder d = Encoding.UTF8.GetDecoder(); d.GetChars(byData, 0, byData.Length, charData, 0); //Char2Byte Encoder e = Encoding.UTF8.GetEncoder(); e.GetBytes(charData, 0, charData.Length, byData, 0, true);
2）StreamRead的使用：
FileStream aFile = new FileStream("Log.txt", FileMode.Open); StreamReader sr = new StreamReader(aFile); line = sr.ReadLine(); // Read data in line by line. while (line != null) { Console.WriteLine(line); line = sr.ReadLine(); } sr.Close();
3）StreamWrite的使用：
FileStream aFile = new FileStream("Log.txt", FileMode.OpenOrCreate); StreamWriter sw = new StreamWriter(aFile); sw.WriteLine("now： {0} ",DateTime.Now.ToLongDateString()); sw.Close();
2、读取分隔符文件
using System; using System.Collections.Generic; using System.Linq; using System.Text; using System.IO; namespace CommaValues { class Program { private static List<Dictionary<string, string>> GetData( out List<string> columns) { string line; string[] stringArray; char[] charArray = new char[] { ',' }; List<Dictionary<string, string>> data = new List<Dictionary<string, string>>(); columns = new List<string>(); try { FileStream aFile = new FileStream(@"....SomeData.txt", FileMode.Open); StreamReader sr = new StreamReader(aFile); // Obtain the columns from the first line. // Split row of data into string array line = sr.ReadLine(); stringArray = line.Split(charArray); for (int x = 0; x <= stringArray.GetUpperBound(0); x++) //GetUpperBound:获取 System.Array 的指定维度的上限。 { columns.Add(stringArray[x]); } line = sr.ReadLine(); while (line != null) { // Split row of data into string array stringArray = line.Split(charArray); Dictionary<string, string> dataRow = new Dictionary<string, string>(); for (int x = 0; x <= stringArray.GetUpperBound(0); x++) { dataRow.Add(columns[x], stringArray[x]); } data.Add(dataRow); line = sr.ReadLine(); } sr.Close(); return data; } catch (IOException ex) { Console.WriteLine("An IO exception has been thrown!"); Console.WriteLine(ex.ToString()); Console.ReadLine(); return data; } } static void Main(string[] args) { List<string> columns; List<Dictionary<string, string>> myData = GetData(out columns); foreach (string column in columns) { Console.Write("{0,-20}", column); } Console.WriteLine(); foreach (Dictionary<string, string> row in myData) { foreach (string column in columns) { Console.Write("{0,-20}", row[column]); } Console.WriteLine(); } Console.ReadKey(); } } }
3、处理压缩|解压文件
using System; using System.Collections.Generic; using System.Linq; using System.Text; using System.IO; using System.IO.Compression; namespace Compressor { class Program { static void SaveCompressedFile(string filename, string data) { FileStream fileStream = new FileStream(filename, FileMode.Create, FileAccess.Write); GZipStream compressionStream = new GZipStream(fileStream, CompressionMode.Compress); StreamWriter writer = new StreamWriter(compressionStream); writer.Write(data); writer.Close(); } static string LoadCompressedFile(string filename) { FileStream fileStream = new FileStream(filename, FileMode.Open, FileAccess.Read); GZipStream compressionStream = new GZipStream(fileStream, CompressionMode.Decompress); StreamReader reader = new StreamReader(compressionStream); string data = reader.ReadToEnd(); reader.Close(); return data; } static void Main(string[] args) { try { string filename = "compressedFile.txt"; Console.WriteLine( "Enter a string to compress (will be repeated 100 times):"); string sourceString = Console.ReadLine(); StringBuilder sourceStringMultiplier = new StringBuilder(sourceString.Length * 100); for (int i = 0; i < 100; i++) { sourceStringMultiplier.Append(sourceString); } sourceString = sourceStringMultiplier.ToString(); Console.WriteLine("Source data is {0} bytes long.", sourceString.Length); SaveCompressedFile(filename, sourceString); Console.WriteLine(" Data saved to {0}.", filename); FileInfo compressedFileData = new FileInfo(filename); Console.WriteLine("Compressed file is {0} bytes long.", compressedFileData.Length); string recoveredString = LoadCompressedFile(filename); recoveredString = recoveredString.Substring( 0, recoveredString.Length / 100); Console.WriteLine(" Recovered data: {0}", recoveredString); Console.ReadKey(); } catch (IOException ex) { Console.WriteLine("An IO exception has been thrown!"); Console.WriteLine(ex.ToString()); Console.ReadKey(); } } } }
4、序列化|反序列化（IFormatter） ：类默认是不允许序列化的，要进行序列化必须给类添加 [Serializable]属性，不想序列化特殊字段可以添加 [NonSerialized]属性
1）System.Runtime.Serialization.Formatters.Binary下BinaryFormatter类把二进制数据序列化为对象。
// Get serializer. IFormatter serializer = new BinaryFormatter(); // Serialize products. FileStream saveFile = new FileStream("Products.bin", FileMode.Create, FileAccess.Write); serializer.Serialize(saveFile, products); saveFile.Close(); // Deserialize products. FileStream loadFile = new FileStream("Products.bin", FileMode.Open, FileAccess.Read); List<Product> savedProducts = serializer.Deserialize(loadFile) as List<Product>; loadFile.Close();
2）System.Runtime.Serialization.Formatters.Soap下SoapFormatter类把Soap格式的XML数据序列化为对象。(需要给工程中的引用，添加引用中选择“程序集”，找到它并添加)
3)System.Web.UI下ObjectStateFormatter类用于在ASP.Net中序列化viewState。
4）NetDataConstractSerializer类用于序列化WCF数据合同。
5、监控文件（FileSystemWatcher）
1)设置完属性和事件之后，将EnableRaisingEvents属性设置为True，就可以开始监控操作。
定义文件监视器：
private FileSystemWatcher watcher;
定义显示监视器提示内容的委托和异步调用的函数
private delegate void UpdateWatchTextDelegate(string newText); public void UpdateWatchText(string newText) { }
设置属性：
{ watcher.Path = Path.GetDirectoryName(txtLocation.Text); watcher.Filter = Path.GetFileName(txtLocation.Text); watcher.NotifyFilter = NotifyFilters.LastWrite | NotifyFilters.FileName | NotifyFilters.Size; // Begin watching. watcher.EnableRaisingEvents = true; }
设置事件
this.watcher = new FileSystemWatcher(); this.watcher.Deleted += new FileSystemEventHandler(this.OnDelete); this.watcher.Renamed += new RenamedEventHandler(this.OnRenamed); this.watcher.Changed += new FileSystemEventHandler(this.OnChanged); this.watcher.Created += new FileSystemEventHandler(this.OnCreate);
定义触发的相应事件：
// Define the event handlers. public void OnChanged(object source, FileSystemEventArgs e) { try { StreamWriter sw = new StreamWriter("C:/FileLogs/Log.txt", true); sw.WriteLine("File: {0} {1}", e.FullPath, e.ChangeType.ToString()); sw.Close(); this.BeginInvoke(new UpdateWatchTextDelegate(UpdateWatchText), //在创建控件的基础句柄所在线程上，用指定的参数异步执行指定委托。 "Wrote change event to log"); } catch (IOException) { this.BeginInvoke(new UpdateWatchTextDelegate(UpdateWatchText), "Error Writing to log"); } } public void OnRenamed(object source, RenamedEventArgs e) { try { StreamWriter sw = new StreamWriter("C:/FileLogs/Log.txt", true); sw.WriteLine("File renamed from {0} to {1}", e.OldName, e.FullPath); sw.Close(); this.BeginInvoke(new UpdateWatchTextDelegate(UpdateWatchText), "Wrote renamed event to log"); } catch (IOException) { this.BeginInvoke(new UpdateWatchTextDelegate(UpdateWatchText), "Error Writing to log"); } } public void OnDelete(object source, FileSystemEventArgs e) { try { StreamWriter sw = new StreamWriter("C:/FileLogs/Log.txt", true); sw.WriteLine("File: {0} Deleted", e.FullPath); sw.Close(); this.BeginInvoke(new UpdateWatchTextDelegate(UpdateWatchText), "Wrote delete event to log"); } catch (IOException) { this.BeginInvoke(new UpdateWatchTextDelegate(UpdateWatchText), "Error Writing to log"); } } public void OnCreate(object source, FileSystemEventArgs e) { try { StreamWriter sw = new StreamWriter("C:/FileLogs/Log.txt", true); sw.WriteLine("File: {0} Created", e.FullPath); sw.Close(); this.BeginInvoke(new UpdateWatchTextDelegate(UpdateWatchText), "Wrote create event to log"); } catch (IOException) { this.BeginInvoke(new UpdateWatchTextDelegate(UpdateWatchText), "Error Writing to log"); } }