Directory.Exists(String) Metod

public:
 static bool Exists(System::String ^ path);

public static bool Exists(string path);

public static bool Exists(string? path);

static member Exists : string -> bool

Public Shared Function Exists (path As String) As Boolean

Parametrar

Returer

true om path refererar till en befintlig katalog, false om katalogen inte finns eller om ett fel inträffar när du försöker avgöra om den angivna katalogen finns.

Exempel

I följande exempel tas en matris med fil- eller katalognamn på kommandoraden, avgör vilken typ av namn den är och bearbetar den på rätt sätt.

// 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);	
    }
}

module RecursiveFileProcessor

open System.IO

// Insert logic for processing found files here.
let processFile path =
    printfn $"Processed file '%s{path}'."

// Process all files in the directory passed in, recurse on any directories
// that are found, and process the files they contain.
let rec processDirectory targetDirectory =
    // Process the list of files found in the directory.
    let fileEntries = Directory.GetFiles targetDirectory
    for fileName in fileEntries do
        processFile fileName

    // Recurse into subdirectories of this directory.
    let subdirectoryEntries = Directory.GetDirectories targetDirectory
    for subdirectory in subdirectoryEntries do
        processDirectory subdirectory

[<EntryPoint>]
let main args =
    for path in args do
        if File.Exists path then
            // This path is a file
            processFile path
        elif Directory.Exists path then
            // This path is a directory
            processDirectory path
        else
            printfn $"{path} is not a valid file or directory."
    0

' For File.Exists, Directory.Exists 

Imports System.IO
Imports System.Collections

Public Class RecursiveFileProcessor

    Public Overloads Shared Sub Main(ByVal args() As String)
        Dim path As String
        For Each path In args
            If File.Exists(path) Then
                ' This path is a file.
                ProcessFile(path)
            Else
                If Directory.Exists(path) Then
                    ' This path is a directory.
                    ProcessDirectory(path)
                Else
                    Console.WriteLine("{0} is not a valid file or directory.", path)
                End If
            End If
        Next path
    End Sub


    ' Process all files in the directory passed in, recurse on any directories 
    ' that are found, and process the files they contain.
    Public Shared Sub ProcessDirectory(ByVal targetDirectory As String)
        Dim fileEntries As String() = Directory.GetFiles(targetDirectory)
        ' Process the list of files found in the directory.
        Dim fileName As String
        For Each fileName In fileEntries
            ProcessFile(fileName)

        Next fileName
        Dim subdirectoryEntries As String() = Directory.GetDirectories(targetDirectory)
        ' Recurse into subdirectories of this directory.
        Dim subdirectory As String
        For Each subdirectory In subdirectoryEntries
            ProcessDirectory(subdirectory)
        Next subdirectory

    End Sub

    ' Insert logic for processing found files here.
    Public Shared Sub ProcessFile(ByVal path As String)
        Console.WriteLine("Processed file '{0}'.", path)
    End Sub
End Class

Kommentarer

Parametern path tillåts ange relativ eller absolut sökvägsinformation. Relativ sökvägsinformation tolkas som relativ till den aktuella arbetskatalogen.

Avslutande blanksteg tas bort från slutet av parametern path innan du kontrollerar om katalogen finns.

Parameterns path skiftlägeskänslighet motsvarar det filsystem där koden körs. Det är till exempel skiftlägeskänsligt på NTFS (standard Windows filsystem) och skiftlägeskänsligt på Linux-filsystem.

Om du inte har minst skrivskyddad behörighet till katalogen Exists returnerar falsemetoden .

Metoden Exists returnerar false om något fel inträffar när du försöker avgöra om den angivna filen finns. Detta kan inträffa i situationer som skapar undantag som att skicka ett filnamn med ogiltiga tecken eller för många tecken, en disk som misslyckas eller saknas eller om anroparen inte har behörighet att läsa filen.

Se även

• DirectoryInfo
• Fil- och ström-I/O
• Anvisningar: Läsa text från en fil
• Anvisningar: Skriva text till en fil