C#认识/理解/运用 StreamReader,StreamWriter,StringReader,StreamWriter

 

题记

StreamReader,StreamWriter,StringReader,StreamWriter 每次看到这几个词的时候，就会混淆（理解不够深刻），在使用过程中也经常犯浑，为了能更好的理解，写下此文章。

正文

概念

首先，从字面可以看出，StreamReader,StringReader是用来读操作，StreamWriter,StreamWriter是用来写操作。

接下来看这几个类在类库中的层次

上图中，StreamReader,StringReader都派生自TextReader类（TextReader：表示可读取连续字符序列的读取器。抽象基类）

StreamReader从流中读取字符

StringReader从字符串读取字符

上图中，StreamWriter,StreamWriter派生自TextWriter类（TextWriter：表示可以编写一个有序字符序列的编写器。该类为抽象类。）

StreamWriter将字符写入流

StreamWriter将字符写入字符串

代码

reader操作

private static void StringRead()         {             string in_str ="流操作，字符操作，io操作";             string read_str, aParagraph = null;             StringReader sr = new StringReader(in_str);             while (true)             {                 read_str = sr.ReadLine();                 if (read_str != null)                 {                     aParagraph = aParagraph + in_str + " ";                 }                 else                 {                     aParagraph = aParagraph + "\n";                     break;                 }             }         }         private static void StreamRead()         {             Stream rStream = new FileStream(@"E:/20120214.txt", FileMode.Open);             StreamReader sr = new StreamReader(rStream, Encoding.UTF8);             //从流中读取字符             string result = sr.ReadToEnd();             //释放资源             sr.Close();             rStream.Close();         }

writer操作

private static void StreamWriter()         {             string in_str = DateTime.Now.ToString("MM-dd HH:mm:ss:fff");             //第二个参数  是否追加             StreamWriter sw = new StreamWriter(@"E:/20120214.txt",true,Encoding.Default);             sw.Write(in_str);             sw.Flush();             sw.Close();         }                  private static void StringWriter()         {                        StringWriter sw = new StringWriter();             sw.Write("文字，学习，文字，c#");             sw.Close();         }

来自：http://www.cnblogs.com/zhxhdean/archive/2012/02/20/2359605.html