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1 楚广明 C# 简明教程 Blog: 楚广明 C# 简明教程第 1 页版本 V1.0 1

2 Module 6: Input/Output 楚广明 C# 简明教程第 2 页版本 V1.0 2

3 Review 在这一章中, 我们将主要学习如何使用 Microsoft.NET FrameWork 框架下的 IO 操作, 基本的 IO 操作将包括文件与目录的读取压缩数据流和隔离文件系统楚广明 C# 简明教程第 3 页版本 V1.0 3

4 Exam objectives in this chapter -1 Access Files and folders by using the File System Classes File Class and FileInfo class Directory class and DirectoryInfo class DriveInfo class and DriveType enumeration FileSystemInfo class and FileSystemWatcher class Path class ErrorEventArgs class and ErrorEventHandler delegate RenamedEventArgs class and RenamedEventHandler delegate 楚广明 C# 简明教程第 4 页版本 V1.0 4

5 Exam objectives in this chapter -2 Manage byte streams by using Stream classes FileStream class Stream class MemoryStream class BufferedStream class Manage the.net Framework application data by using Reader and Writer classes StringReader class and StringWriter class TextReader class and TextWriter class StreamReader class and StreamWriter class BinaryReader class and BinaryWriter class 楚广明 C# 简明教程第 5 页版本 V1.0 5

6 Exam objectives in this chapter -3 Compress or decompress stream information in a.net Framework application and improve the security of application data by using isolated storage IsolatedStorageFile class IsolatedStorageFileStream class DeflateStream class GZipStream class 楚广明 C# 简明教程第 6 页版本 V1.0 6

7 Before you Begin To Complate the lessons in this chapter,you should be familiar with Microsoft C# and be comfortable with the following tasks: Create a console application in Microsoft Visual Studio using C# Add references to System class libraries to a project Create text files 楚广明 C# 简明教程第 7 页版本 V1.0 7

8 Lesson 1:Navigating the file System 对每一个开发人员来说, 对文件系统进行操作是他们每天工作中的一部分这些工作包括浏览与收集盘符目录文件在文件系统中的变化. 楚广明 C# 简明教程第 8 页版本 V1.0 8

9 What are the file system classes? 当我们深入观察 System.IO 这个命名空间时您会发现它是由一系列针对文件目录驱动器进行操作与维护的类的集合 System.IO 这个命名空间中分为二种类型的类 : 信息类与工具类 (Informational and utility) 大部分的信息类继承之 FileSystemInfo 这个 File 系统的基类. 这些类主要用于获取文件目录驱动器的相关信息,FileInfo 与 DirectoryInfo 就是其中的二个类 DriveInfo 这个类就要用于描述文件系统上的驱动器, 尽管这也是一个信息类, 但它并非继承之 FileSystemInfo 这个类, 因为我们对驱动器是无法执行诸如 ( 删除文件目录这样的操作 ) 工具类提供了一些静态的方法用于对系统中的文件目录路径进行操作, 工具类主要包括了 File Directory Path 这三个类楚广明 C# 简明教程第 9 页版本 V1.0 9

10 The FileSystemInfo Class 楚广明 C# 简明教程第 10 页版本 V1.0 The FileSystemInfo class Provides the basic functionality for all informational file system classes 10

11 The FileInfo Class 楚广明 C# 简明教程第 11 页版本 V1.0 THE FileSystemInfo class provides the basic functionality for all informational file sytem classes 11

12 The FileInfo Class 楚广明 C# 简明教程第 12 页版本 V1.0 12

13 FileSystemInfo 与 FileInfo 的关系楚广明 C# 简明教程第 13 页版本 V1.0 13

14 How to Get Information about a file To obtain information about a specific file,fllow this procedure: Create a new FileInfo object by usinig the path to the file Access the FileInfo object s properties For example you can check whether a file exists by calling the FileInfo object s Exist property,as shown in the following code: 楚广明 C# 简明教程第 14 页版本 V1.0 14

15 How to copy a file In addition to accessing data about a file,the FileInfo object allows operations to be performed on the file.again,once a valid FileInfo object is obtained,all you have to do is call the CopyTo method to make a copy of your file, as the fllowing code example shows: 楚广明 C# 简明教程第 15 页版本 V1.0 15

16 The DirectoryInfo class 楚广明 C# 简明教程第 16 页版本 V1.0 The DirectoryInfo class provides the basic functionality to access and manipulate a single direcotyr in the file system 16

17 How to Enumerate files in a Directory Accessing the files in directory is much like accessing file information,the following steps show how to enumerate the files in a directory: Create a valid DirectoryInfo object by using the path to the directory Call the GetFiles method to enumerate the files in the directory 楚广明 C# 简明教程第 17 页版本 V1.0 17

18 The DriveInfo class 楚广明 C# 简明教程第 18 页版本 V1.0 18

19 The DriveInfo class 楚广明 C# 简明教程第 19 页版本 V1.0 19

20 How to Enumerate Drives You follow this procedure to access the drives in a system: Call the static GetDrives method of the DriveInfo class Loop through the array of DriveInfo objects returned by GetDrives 楚广明 C# 简明教程第 20 页版本 V1.0 20

21 The Path class 楚广明 C# 简明教程第 21 页版本 V1.0 21

22 How to change a file extension If you want to get and change the extension of a file,you can do so with the path class as shown in the following code snippet: 楚广明 C# 简明教程第 22 页版本 V1.0 22

23 The FileSystemWatcher Class The FileSystemWatcher class provides methods for monitoring file system directories for changes 楚广明 C# 简明教程第 23 页版本 V1.0 23

24 The FileSystemWatcher Class 楚广明 C# 简明教程第 24 页版本 V1.0 24

25 The FileSystemWatcher Class 楚广明 C# 简明教程第 25 页版本 V1.0 25

26 How to Monitor a Directory for Changes 楚广明 C# 简明教程第 26 页版本 V1.0 26

27 Lesson2:Reading and Writing Files Reading and writing files are two of the most common tasks in the world of development as a.net developer,you need to know how to read and write files.the.net framework makes it easy to perform these taskes 楚广明 C# 简明教程第 27 页版本 V1.0 27

28 Understanding Streams 楚广明 C# 简明教程第 28 页版本 V1.0 Streams are a common way to deal with both sequential and random access to data within the.net framework.streams are used throughout different parts of the Framework.they begin with an abstract class 28

29 Understanding Streams 楚广明 C# 简明教程第 29 页版本 V1.0 29

30 Stream class All other stream classes in the.net framework derive from the stream class.these derived classes include the following: 楚广明 C# 简明教程第 30 页版本 V1.0 30

31 Stream demo 楚广明 C# 简明教程第 31 页版本 V1.0 31

32 What class facilitate reading and writing data? A number of classes take part in the process of reading and writing files.most operation begin with the File class.this class expose static methods that allow for opening and creating files.the File class can perform servral types of operations: Atomic operations to read or write all the contents of a file Operations to create or open files for reading Operations to create or open files for writing Simple file Operations(File.Exists File.Delete and so on) 楚广明 C# 简明教程第 32 页版本 V1.0 When a file is opened or created,the file class can return several types of objects. The most runidmentary of these is the FileStream object. This is a simple stream class,but it represents a file in the file System In addition the File class also has methods that reutrn StreamReaders and StreamWriters These classes wrap a FileStream to Support sequential reading and writing to a stream 32

33 The File Class 楚广明 C# 简明教程第 33 页版本 V1.0 33

34 The File Class 楚广明 C# 简明教程第 34 页版本 V1.0 34

35 The Directory Class As it does with the File Class,the.net framework supports the Directory class,which presents a static/shared interface of manipulating and creating directories in the file system. The Directory class provides the basic functionality to open file streams for reading and writing.shows the most important directory static/shared methods 楚广明 C# 简明教程第 35 页版本 V1.0 35

36 The Directory class 楚广明 C# 简明教程第 36 页版本 V1.0 36

37 The Directory class 楚广明 C# 简明教程第 37 页版本 V1.0 37

38 The FileAccess enumeration 楚广明 C# 简明教程第 38 页版本 V1.0 38

39 The FileMode Enumeration 楚广明 C# 简明教程第 39 页版本 V1.0 39

40 The FileStream class 楚广明 C# 简明教程第 40 页版本 V1.0 40

41 The Filestream class 楚广明 C# 简明教程第 41 页版本 V1.0 41

42 The FileStream class 楚广明 C# 简明教程第 42 页版本 V1.0 42

43 The FileStream class 楚广明 C# 简明教程第 43 页版本 V1.0 43

44 The StreamReader class 楚广明 C# 简明教程第 44 页版本 V1.0 44

45 The StreamReader class 楚广明 C# 简明教程第 45 页版本 V1.0 45

46 How to Read from a file 楚广明 C# 简明教程第 46 页版本 V1.0 46

47 How to Read from a file Scanning files with this method is especially helpful when looking through very large files 楚广明 C# 简明教程第 47 页版本 V1.0 If you can get everything you need with the File Class s ReadAllText method,why would you use these other methods? The usual reason is that you do not need the entire text file. This approach is especially helpful if you are searching for a particular test for a string that matches,and if you find it, You don t need to load the entire string into memory 47

48 The StreamWriter Class 楚广明 C# 简明教程第 48 页版本 V1.0 48

49 How to Write to a file 楚广明 C# 简明教程第 49 页版本 V1.0 49

Understanding Readers and Writers As shown in the previus sections,streamreader and StreamWriter are classes that make it simple to write to and read from text streams.

50 Understanding Readers and Writers As shown in the previus sections,streamreader and StreamWriter are classes that make it simple to write to and read from text streams.that is the purpose of the reader and writer classes.the StreamReader class derives from the abstract TextReader class.the StreamWriter,not surprisingly,derives from the abstract TextWriter class 楚广明 C# 简明教程第 50 页版本 V1.0 50

51 Understanding Readers and Writers-StringWriter and StringReader 楚广明 C# 简明教程第 51 页版本 V1.0 51

52 Understanding Readers and Writers-BinaryWriter and BinaryReader 楚广明 C# 简明教程第 52 页版本 V1.0 BinaryWriter classes can be used to handle getting binary data to and from streams. For example,if you want to create a new file to store binary data,you can use the BinaryWriter class to write various types of data to a stream like so 52

53 The MemoryStream Class 楚广明 C# 简明教程第 53 页版本 V1.0 53

54 The MemoryStream Class 楚广明 C# 简明教程第 54 页版本 V1.0 54

55 The MemoryStream Class 楚广明 C# 简明教程第 55 页版本 V1.0 55

56 The MemoryStream Class 楚广明 C# 简明教程第 56 页版本 V1.0 56

57 How to use a MemoryStream As you have Seen,Working with Streams of data is an important skill for any developer.unfortunately,often you will need to create a stream before you really need to store it somewhere.the MemoryStream class has the job of helping you create streams in memory.creating a memory stream is as simple as creating a new instance of the memorystream class 楚广明 C# 简明教程第 57 页版本 V1.0 57

58 The BufferedStream class 楚广明 C# 简明教程第 58 页版本 V1.0 58

59 The BufferedStream class 楚广明 C# 简明教程第 59 页版本 V1.0 59

60 The BufferedStream class 楚广明 C# 简明教程第 60 页版本 V1.0 60

61 How to use a BufferedStream 楚广明 C# 简明教程第 61 页版本 V1.0 61

62 Lesson 3:Compressing Streams 楚广明 C# 简明教程第 62 页版本 V1.0 62

63 Introducing the Compression Streams 楚广明 C# 简明教程第 63 页版本 V1.0 63

64 The GZipStream Class 楚广明 C# 简明教程第 64 页版本 V1.0 64

65 The GZipStream Class 楚广明 C# 简明教程第 65 页版本 V1.0 65

66 The GZipStream Class 楚广明 C# 简明教程第 66 页版本 V1.0 66

67 The DeflateStream Class 楚广明 C# 简明教程第 67 页版本 V1.0 67

68 The DeflateStream Class 楚广明 C# 简明教程第 68 页版本 V1.0 68

69 The DeflateStream Class 楚广明 C# 简明教程第 69 页版本 V1.0 69

70 The DeflateStream Class 楚广明 C# 简明教程第 70 页版本 V1.0 70

71 How to Compress Data with a Compression Stream 楚广明 C# 简明教程第 71 页版本 V1.0 71

72 How to Decompress data With a Compresson Stream 楚广明 C# 简明教程第 72 页版本 V1.0 72

73 Lesson4:Working with Isolated storage 楚广明 C# 简明教程第 73 页版本 V1.0 73

Windows XP

Windows XP What is Windows XP Windows is an Operating System An Operating System is the program that controls the hardware of your computer, and gives you an interface that allows you and other programs