Input and Output

Objectives of Input and Output is survey IO facilities in .NET Framework Class Library (file and directory management, text files, binary files, object serialization). It includes IO Library, Files and directories, File System Info, Utility classes, Choice of file/directory class.
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Input and OutputInput and OutputObjectives• Survey IO facilities in .NET Framework Class Library – file and directory management – text files – binary files – object serialization 2IO Library• Input/output library in System.IO namespace• Support provided for: – file and directory management – text files – binary files – simple type conversion to/from binary 3Files and directories• Two primary classes to work with files and directories – perform file system interaction – generally do not manipulate file contents – derived from common base FileSystemInfo DirectoryInfo FileInfo 4 FileSystemInfo • Files and directories have some operations in common – provided in base class FileSystemInfo public abstract class FileSystemInfo ... { public abstract string Name { get; } name public string FullName { get; } public string Extension { get; } public abstract bool Exists { get; } public DateTime CreationTime { get; set; }characteristics public DateTime LastAccessTime { get; set; } public DateTime LastWriteTime { get; set; } public FileAttributes Attributes { get; set; } delete public void Delete() ... ... } 5 DirectoryInfo • DirectoryInfo represents a directory – methods provided to examine and manipulate – inherits common operations from FileSystemInfo public sealed class DirectoryInfo : FileSystemInfo { constructor public DirectoryInfo(string path) ... public DirectoryInfo Parent { get; } navigation public DirectoryInfo Root { get; } public void Create () ...manipulation public void MoveTo (string destDirName) ... public void Delete (bool recursive ) ... public DirectoryInfo CreateSubdirectory(string path ) ... public FileInfo [] GetFiles () ... contents public DirectoryInfo [] GetDirectories () ... public FileSystemInfo[] GetFileSystemInfos() ... ... } 6 FileInfo • FileInfo represents a file – methods provided to examine and manipulate – inherits common operations from FileSystemInfo public sealed class FileInfo : FileSystemInfo { constructor public FileInfo(string fileName) ... length public long Length { get; } public string DirectoryName { get; } location public DirectoryInfo Directory { get; } public FileInfo CopyTo(string destFileName) ...manipulation public FileInfo CopyTo(string destFileName, bool overwrite) ... public void MoveTo(string destFileName) ... ... } 7 Application: List contents • Can examine contents of a directory void List(string path) { DirectoryInfo directory = new DirectoryInfo(path); FileInfo [] files = directory.GetFiles (); contents DirectoryInfo[] directories = directory.GetDirectories(); files foreach (FileInfo f in files) Console.WriteLine(f.Name);directories foreach (DirectoryInfo d in directories) Console.WriteLine(d.Name); } 8 Application: Find file • Can search file system to find specified files void Find(string filename, DirectoryInfo root, ArrayList results) { search ...