本文档已存档,并且将不进行维护。

Directory.Exists 方法

确定给定路径是否引用磁盘上的现有目录。

命名空间: System.IO
程序集: mscorlib(在 mscorlib.dll 中)

public static bool Exists (
	string path
)
public static boolean Exists (
	String path
)
public static function Exists (
	path : String
) : boolean
不适用。

参数

path

要测试的路径。

返回值

如果 path 引用现有目录,则为 true;否则为 false

允许 path 参数指定相对或绝对路径信息。相对路径信息被解释为相对于当前工作目录。

检查该目录是否存在之前,从 path 参数的末尾移除尾随空格。

path 参数不区分大小写。

Exists 方法不执行网络身份验证。如果事先未进行身份验证就查询现有的网络共享,则 Exists 方法将返回 False。

下表列出了其他典型或相关的 I/O 任务的示例。

有关通用 I/O 任务的列表,请参见 通用 I/O 任务

下面的代码示例接受命令行上的一组文件名或目录名,确定名称类型,然后相应地进行处理。

// For File.Exists, Directory.Exists
using System;
using System.IO;
using System.Collections;

public class RecursiveFileProcessor 
{
    public static void Main(string[] args) 
    {
        foreach(string path in args) 
        {
            if(File.Exists(path)) 
            {
                // This path is a file
                ProcessFile(path); 
            }               
            else if(Directory.Exists(path)) 
            {
                // This path is a directory
                ProcessDirectory(path);
            }
            else 
            {
                Console.WriteLine("{0} is not a valid file or directory.", path);
            }        
        }        
    }


    // Process all files in the directory passed in, recurse on any directories 
    // that are found, and process the files they contain.
    public static void ProcessDirectory(string targetDirectory) 
    {
        // Process the list of files found in the directory.
        string [] fileEntries = Directory.GetFiles(targetDirectory);
        foreach(string fileName in fileEntries)
            ProcessFile(fileName);

        // Recurse into subdirectories of this directory.
        string [] subdirectoryEntries = Directory.GetDirectories(targetDirectory);
        foreach(string subdirectory in subdirectoryEntries)
            ProcessDirectory(subdirectory);
    }
        
    // Insert logic for processing found files here.
    public static void ProcessFile(string path) 
    {
        Console.WriteLine("Processed file '{0}'.", path);	    
    }
}

// For File.Exists, Directory.Exists
import System.*;
import System.IO.*;
import System.Collections.*;

public class RecursiveFileProcessor
{
    public static void main(String[] args)
    {
        for (int iCtr = 0; iCtr < args.get_Length(); iCtr++) {
            String path = args[iCtr];
            if (File.Exists(path)) {
                // This path is a file
                ProcessFile(path);
            }
            else {
                if (Directory.Exists(path)) {
                    // This path is a directory
                    ProcessDirectory(path);
                }
                else {
                    Console.WriteLine("{0} is not a valid file or directory.",
                        path);
                }
            }
        }
    } //main

    // Process all files in the directory passed in, recurse on any directories 
    // that are found, and process the files they contain.
    public static void ProcessDirectory(String targetDirectory)
    {
        // Process the list of files found in the directory.
        String fileEntries[] = Directory.GetFiles(targetDirectory);
        for (int iCtr1 = 0; iCtr1 < fileEntries.get_Length(); iCtr1++) {
            String fileName = fileEntries[iCtr1];
            ProcessFile(fileName);
        }
        // Recurse into subdirectories of this directory.
        String subDirectoryEntries[] = 
            Directory.GetDirectories(targetDirectory);
        for (int iCtr2 = 0; iCtr2 < subDirectoryEntries.get_Length(); 
            iCtr2++) {
            String subDirectory = subDirectoryEntries[iCtr2];
            ProcessDirectory(subDirectory);
        }
    } //ProcessDirectory

    // Insert logic for processing found files here.
    public static void ProcessFile(String path)
    {
        Console.WriteLine("Processed file '{0}'.", path);
    } //ProcessFile
} //RecursiveFileProcessor

//For Directory.GetFiles and Directory.GetDirectories
import System;
import System.IO;
import System.Collections;

// For File.Exists, Directory.Exists 
// Takes an array of file names or directory names on the command line.  
// Determines what kind of name it is and processes it appropriately
public class RecursiveFileProcessor {
    public static function Main(args : String[]) : void  {
        for(var i : int in args) {
            var path : String = args[i];
            if (File.Exists(path)) {
                // This path is a file
                ProcessFile(path); 
            }               
            else if(Directory.Exists(path)) {
                // This path is a directory
                ProcessDirectory(path);
            }
            else {
                Console.WriteLine("{0} is not a valid file or directory.", path);
            }        
        }        
    }


    // Process all files in the directory passed in, and recurse on any directories 
    // that are found to process the files they contain
    public static function ProcessDirectory(targetDirectory : String) : void  {
        // Process the list of files found in the directory
        var fileEntries : String [] = Directory.GetFiles(targetDirectory);
        for (var i : int in fileEntries)
    	    ProcessFile(fileEntries[i]);

        // Recurse into subdirectories of this directory
        var subdirectoryEntries : String[] = Directory.GetDirectories(targetDirectory);
        for (i in subdirectoryEntries)
            ProcessDirectory(subdirectoryEntries[i]);
    }
        
    // Real logic for processing found files would go here.
    public static function ProcessFile(path : String) : void  {
        Console.WriteLine("Processed file '{0}'.", path);	    
    }
}

// For JScript there is no 'Main' routine defined and hence the command line arguments
// have to be obtained with a call to System.Environment.GetCommandLineArgs
RecursiveFileProcessor.Main(System.Environment.GetCommandLineArgs());

Windows 98, Windows Server 2000 SP4, Windows CE, Windows Millennium Edition, Windows Mobile for Pocket PC, Windows Mobile for Smartphone, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition

Windows Vista、Microsoft Windows XP SP2 和 Windows Server 2003 SP1 支持 Microsoft .NET Framework 3.0。

.NET Framework

受以下版本支持:3.0、2.0、1.1、1.0

.NET Compact Framework

受以下版本支持:2.0、1.0

XNA Framework

受以下版本支持:1.0
显示: