FileInfo.CopyTo 方法

定義

命名空間:

System.IO

組件:

System.Runtime.dll

複製現有的檔案到新的檔案。

多載

CopyTo(String)	複製現有的檔案到新的檔案，不允許覆寫現有的檔案。
CopyTo(String, Boolean)	複製現有的檔案到新檔案，允許覆寫現有的檔案。

CopyTo(String)

來源:

FileInfo.cs

複製現有的檔案到新的檔案，不允許覆寫現有的檔案。

public:
 System::IO::FileInfo ^ CopyTo(System::String ^ destFileName);

public System.IO.FileInfo CopyTo (string destFileName);

member this.CopyTo : string -> System.IO.FileInfo

Public Function CopyTo (destFileName As String) As FileInfo

參數

destFileName

String

要複製的目標新檔案名稱。

傳回

FileInfo

有完整路徑的新檔案。

例外狀況

ArgumentException

.NET Framework 和 2.1 之前的 .NET Core 版本是destFileName空的、只包含空格符，或包含無效字元。

IOException

發生錯誤，或者目的檔案已經存在。

SecurityException

呼叫端沒有必要的權限。

ArgumentNullException

destFileName 為 null。

UnauthorizedAccessException

傳入了目錄路徑，或者檔案正要移至不同的磁碟機。

DirectoryNotFoundException

destFileName 中指定的目錄不存在。

PathTooLongException

指定的路徑、檔案名稱，或兩者都超出系統定義的長度上限。

NotSupportedException

字串內的 destFileName 包含冒號 (:)，但未指定磁碟區。

範例

下列範例示範 方法的兩個 CopyTo 多載。

using namespace System;
using namespace System::IO;

int main()
{
   String^ path = "c:\\MyTest.txt";
   String^ path2 = "c:\\MyTest.txttemp";
   FileInfo^ fi1 = gcnew FileInfo( path );
   FileInfo^ fi2 = gcnew FileInfo( path2 );
   try
   {
      // Create the file and clean up handles.
      FileStream^ fs = fi1->Create();
      if ( fs )
         delete (IDisposable^)fs;
      
      //Ensure that the target does not exist.
      fi2->Delete();
      
      //Copy the file.
      fi1->CopyTo( path2 );
      Console::WriteLine( "{0} was copied to {1}.", path, path2 );
      
      //Try to copy it again, which should succeed.
      fi1->CopyTo( path2, true );
      Console::WriteLine( "The second Copy operation succeeded, which is expected." );
   }
   catch ( Exception^ ) 
   {
      Console::WriteLine( "Double copying was not allowed, which is not expected." );
   }
}
//This code produces output similar to the following; 
//results may vary based on the computer/file structure/etc.:
//
//The second Copy operation succeeded, which is expected.

using System;
using System.IO;

class Test
{

    public static void Main()
    {
        string path = @"c:\SoureFile.txt";
        string path2 = @"c:\NewFile.txt";
        FileInfo fi1 = new FileInfo(path);
        FileInfo fi2 = new FileInfo(path2);

        try
        {
            // Create the source file.
            using (FileStream fs = fi1.Create()) { }

            //Ensure that the target file does not exist.
            if (File.Exists(path2))
            {
                fi2.Delete();
            }

            //Copy the file.f
            fi1.CopyTo(path2);
            Console.WriteLine("{0} was copied to {1}.", path, path2);
        }
        catch (IOException ioex)
        {
            Console.WriteLine(ioex.Message);
        }
    }
}

Imports System.IO

Public Class Test

    Public Shared Sub Main()
        'Specify the directories you want to manipulate.
        Dim path As String = "c:\SourceFile.txt"
        Dim path2 As String = "c:\NewFile.txt"
        Dim fi As FileInfo = New FileInfo(path)
        Dim fi2 As FileInfo = New FileInfo(path2)

        Try
            Using fs As FileStream = fi.Create()
            End Using

            'Ensure that the target does not exist.
            If File.Exists(path2) Then
                fi2.Delete()
            End If
            
            'Copy the file.
            fi.CopyTo(path2)
            Console.WriteLine("{0} was copied to {1}.", path, path2)

        Catch ioex As IOException
            Console.WriteLine(ioex.Message)
        End Try
    End Sub
End Class

下列範例示範如何將一個檔案複製到另一個檔案，如果目的地檔案已經存在，則會擲回例外狀況。

using namespace System;
using namespace System::IO;
int main()
{
   try
   {
      
      // Create a reference to a file, which might or might not exist.
      // If it does not exist, it is not yet created.
      FileInfo^ fi = gcnew FileInfo( "temp.txt" );
      
      // Create a writer, ready to add entries to the file.
      StreamWriter^ sw = fi->AppendText();
      sw->WriteLine( "Add as many lines as you like..." );
      sw->WriteLine( "Add another line to the output..." );
      sw->Flush();
      sw->Close();
      
      // Get the information out of the file and display it.
      StreamReader^ sr = gcnew StreamReader( fi->OpenRead() );
      Console::WriteLine( "This is the information in the first file:" );
      while ( sr->Peek() != -1 )
            Console::WriteLine( sr->ReadLine() );
      
      // Copy this file to another file. The file will not be overwritten if it already exists.
      FileInfo^ newfi = fi->CopyTo( "newTemp.txt" );
      
      // Get the information out of the new file and display it.* sr = new StreamReader(newfi->OpenRead());
      Console::WriteLine( "{0}This is the information in the second file:", Environment::NewLine );
      while ( sr->Peek() != -1 )
            Console::WriteLine( sr->ReadLine() );
   }
   catch ( Exception^ e ) 
   {
      Console::WriteLine( e->Message );
   }

}
//This code produces output similar to the following; 
//results may vary based on the computer/file structure/etc.:
//
//This is the information in the first file:
//Add as many lines as you like...
//Add another line to the output...
//
//This is the information in the second file:

using System;
using System.IO;

public class CopyToTest
{
    public static void Main()
    {
        try
        {
            // Create a reference to a file, which might or might not exist.
            // If it does not exist, it is not yet created.
            FileInfo fi = new FileInfo("temp.txt");
            // Create a writer, ready to add entries to the file.
            StreamWriter sw = fi.AppendText();
            sw.WriteLine("Add as many lines as you like...");
            sw.WriteLine("Add another line to the output...");
            sw.Flush();
            sw.Close();
            // Get the information out of the file and display it.
            StreamReader sr = new StreamReader(fi.OpenRead());
            Console.WriteLine("This is the information in the first file:");
            while (sr.Peek() != -1)
                Console.WriteLine(sr.ReadLine());
            // Copy this file to another file. The file will not be overwritten if it already exists.
            FileInfo newfi = fi.CopyTo("newTemp.txt");
            // Get the information out of the new file and display it.
            sr = new StreamReader(newfi.OpenRead());
            Console.WriteLine("{0}This is the information in the second file:", Environment.NewLine);
            while (sr.Peek() != -1)
                Console.WriteLine(sr.ReadLine());
        }
        catch(Exception e)
        {
            Console.WriteLine(e.Message);
        }
    }
}
//This code produces output similar to the following;
//results may vary based on the computer/file structure/etc.:
//
//This is the information in the first file:
//Add as many lines as you like...
//Add another line to the output...

//This is the information in the second file:
//Add as many lines as you like...
//Add another line to the output...

Imports System.IO

Public Class CopyToTest
    Public Shared Sub Main()
        Try
            ' Create a reference to a file, which might or might not exist.
            ' If it does not exist, it is not yet created.
            Dim fi As New FileInfo("temp.txt")
            ' Create a writer, ready to add entries to the file.
            Dim sw As StreamWriter = fi.AppendText()
            sw.WriteLine("Add as many lines as you like...")
            sw.WriteLine("Add another line to the output...")
            sw.Flush()
            sw.Close()
            ' Get the information out of the file and display it.
            Dim sr As New StreamReader(fi.OpenRead())
            Console.WriteLine("This is the information in the first file:")
            While sr.Peek() <> -1
                Console.WriteLine(sr.ReadLine())
            End While
            ' Copy this file to another file.
            Dim newfi As FileInfo = fi.CopyTo("newTemp.txt")
            ' Get the information out of the new file and display it.
            sr = New StreamReader(newfi.OpenRead())
            Console.WriteLine("{0}This is the information in the second file:", Environment.NewLine)
            While sr.Peek() <> -1
                Console.WriteLine(sr.ReadLine())
            End While
        Catch e As Exception
            Console.WriteLine(e.Message)
        End Try
    End Sub
End Class
'This code produces output similar to the following; 
'results may vary based on the computer/file structure/etc.:
'
'This is the information in the first file:
'Add as many lines as you like...
'Add another line to the output...
'
'This is the information in the second file:
'Add as many lines as you like...
'Add another line to the output...

備註

CopyTo(String, Boolean)使用方法來允許覆寫現有的檔案。

警告

請盡可能避免使用簡短檔名 (，例如XXXXXX~1.XXX) 此方法。 如果兩個檔案具有相等的簡短檔名，則此方法可能會失敗並引發例外狀況和/或導致不想要的行為

另請參閱

• 檔案和資料流 I/O
• 作法：讀取檔案中的文字
• 作法：將文字寫入檔案
• 作法：讀取和寫入新建立的資料檔案

CopyTo(String, Boolean)

來源:

FileInfo.cs

複製現有的檔案到新檔案，允許覆寫現有的檔案。

public:
 System::IO::FileInfo ^ CopyTo(System::String ^ destFileName, bool overwrite);

public System.IO.FileInfo CopyTo (string destFileName, bool overwrite);

member this.CopyTo : string * bool -> System.IO.FileInfo

Public Function CopyTo (destFileName As String, overwrite As Boolean) As FileInfo

參數

destFileName

String

要複製的目標新檔案名稱。

overwrite

Boolean

若允許覆寫現有檔案，則為 true，否則為 false。

傳回

FileInfo

新檔案，或現有檔案的覆寫 (如果 overwrite 為 true)。 如果檔案存在而且 overwrite 為 false，則會擲回 IOException。

例外狀況

ArgumentException

.NET Framework 和 2.1 之前的 .NET Core 版本是destFileName空的、只包含空格符，或包含無效字元。

IOException

發生錯誤，或者目的檔案已經存在，而且 overwrite 為 false。

SecurityException

呼叫端沒有必要的權限。

ArgumentNullException

destFileName 為 null。

DirectoryNotFoundException

destFileName 中指定的目錄不存在。

UnauthorizedAccessException

傳入了目錄路徑，或者檔案正要移至不同的磁碟機。

PathTooLongException

指定的路徑、檔案名稱，或兩者都超出系統定義的長度上限。

NotSupportedException

destFileName 在字串的中間包含一個冒號 (:)。

範例

下列範例示範 方法的兩個 CopyTo 多載。

using namespace System;
using namespace System::IO;

int main()
{
   String^ path = "c:\\MyTest.txt";
   String^ path2 = "c:\\MyTest.txttemp";
   FileInfo^ fi1 = gcnew FileInfo( path );
   FileInfo^ fi2 = gcnew FileInfo( path2 );
   try
   {
      // Create the file and clean up handles.
      FileStream^ fs = fi1->Create();
      if ( fs )
         delete (IDisposable^)fs;
      
      //Ensure that the target does not exist.
      fi2->Delete();
      
      //Copy the file.
      fi1->CopyTo( path2 );
      Console::WriteLine( "{0} was copied to {1}.", path, path2 );
      
      //Try to copy it again, which should succeed.
      fi1->CopyTo( path2, true );
      Console::WriteLine( "The second Copy operation succeeded, which is expected." );
   }
   catch ( Exception^ ) 
   {
      Console::WriteLine( "Double copying was not allowed, which is not expected." );
   }
}
//This code produces output similar to the following; 
//results may vary based on the computer/file structure/etc.:
//
//The second Copy operation succeeded, which is expected.

using System;
using System.IO;

class Test
{

    public static void Main()
    {
        string path = @"c:\SoureFile.txt";
        string path2 = @"c:\NewFile.txt";
        FileInfo fi1 = new FileInfo(path);
        FileInfo fi2 = new FileInfo(path2);

        try
        {
            // Create the source file.
            using (FileStream fs = fi1.Create()) { }

            //Ensure that the target file does not exist.
            if (File.Exists(path2))
            {
                fi2.Delete();
            }

            //Copy the file.f
            fi1.CopyTo(path2);
            Console.WriteLine("{0} was copied to {1}.", path, path2);
        }
        catch (IOException ioex)
        {
            Console.WriteLine(ioex.Message);
        }
    }
}

Imports System.IO

Public Class Test

    Public Shared Sub Main()
        'Specify the directories you want to manipulate.
        Dim path As String = "c:\SourceFile.txt"
        Dim path2 As String = "c:\NewFile.txt"
        Dim fi As FileInfo = New FileInfo(path)
        Dim fi2 As FileInfo = New FileInfo(path2)

        Try
            Using fs As FileStream = fi.Create()
            End Using

            'Ensure that the target does not exist.
            If File.Exists(path2) Then
                fi2.Delete()
            End If
            
            'Copy the file.
            fi.CopyTo(path2)
            Console.WriteLine("{0} was copied to {1}.", path, path2)

        Catch ioex As IOException
            Console.WriteLine(ioex.Message)
        End Try
    End Sub
End Class

下列範例示範如何將一個檔案複製到另一個檔案，指定是否要覆寫已經存在的檔案。

using namespace System;
using namespace System::IO;
int main()
{
   
   // Create a reference to a file, which might or might not exist.
   // If it does not exist, it is not yet created.
   FileInfo^ fi = gcnew FileInfo( "temp.txt" );
   
   // Create a writer, ready to add entries to the file.
   StreamWriter^ sw = fi->AppendText();
   sw->WriteLine( "Add as many lines as you like..." );
   sw->WriteLine( "Add another line to the output..." );
   sw->Flush();
   sw->Close();
   
   // Get the information out of the file and display it.
   StreamReader^ sr = gcnew StreamReader( fi->OpenRead() );
   Console::WriteLine( "This is the information in the first file:" );
   while ( sr->Peek() != -1 )
      Console::WriteLine( sr->ReadLine() );

   
   // Copy this file to another file. The true parameter specifies
   // that the file will be overwritten if it already exists.
   FileInfo^ newfi = fi->CopyTo( "newTemp.txt", true );
   
   // Get the information out of the new file and display it.* sr = new StreamReader( newfi->OpenRead() );
   Console::WriteLine( "{0}This is the information in the second file:", Environment::NewLine );
   while ( sr->Peek() != -1 )
      Console::WriteLine( sr->ReadLine() );
}
//This code produces output similar to the following; 
//results may vary based on the computer/file structure/etc.:
//
//This is the information in the first file:
//Add as many lines as you like...
//Add another line to the output...
//This is the information in the second file:
//

using System;
using System.IO;

public class CopyToTest
{
    public static void Main()
    {
        // Create a reference to a file, which might or might not exist.
        // If it does not exist, it is not yet created.
        FileInfo fi = new FileInfo("temp.txt");
        // Create a writer, ready to add entries to the file.
        StreamWriter sw = fi.AppendText();
        sw.WriteLine("Add as many lines as you like...");
        sw.WriteLine("Add another line to the output...");
        sw.Flush();
        sw.Close();
        // Get the information out of the file and display it.
        StreamReader sr = new StreamReader( fi.OpenRead() );
        Console.WriteLine("This is the information in the first file:");
        while (sr.Peek() != -1)
            Console.WriteLine( sr.ReadLine() );
        // Copy this file to another file. The true parameter specifies
        // that the file will be overwritten if it already exists.
        FileInfo newfi = fi.CopyTo("newTemp.txt", true);
        // Get the information out of the new file and display it.
        sr = new StreamReader( newfi.OpenRead() );
        Console.WriteLine("{0}This is the information in the second file:", Environment.NewLine);
        while (sr.Peek() != -1)
            Console.WriteLine( sr.ReadLine() );
    }
}
//This code produces output similar to the following;
//results may vary based on the computer/file structure/etc.:
//
//This is the information in the first file:
//Add as many lines as you like...
//Add another line to the output...
//Add as many lines as you like...
//Add another line to the output...

//This is the information in the second file:
//Add as many lines as you like...
//Add another line to the output...
//Add as many lines as you like...
//Add another line to the output...

Imports System.IO

Public Class CopyToTest
    Public Shared Sub Main()
        ' Create a reference to a file, which might or might not exist.
        ' If it does not exist, it is not yet created.
        Dim fi As New FileInfo("temp.txt")
        ' Create a writer, ready to add entries to the file.
        Dim sw As StreamWriter = fi.AppendText()
        sw.WriteLine("Add as many lines as you like...")
        sw.WriteLine("Add another line to the output...")
        sw.Flush()
        sw.Close()
        ' Get the information out of the file and display it.
        Dim sr As New StreamReader(fi.OpenRead())
        Console.WriteLine("This is the information in the first file:")
        While sr.Peek() <> -1
            Console.WriteLine(sr.ReadLine())
        End While
        ' Copy this file to another file. The true parameter specifies 
        ' that the file will be overwritten if it already exists.
        Dim newfi As FileInfo = fi.CopyTo("newTemp.txt", True)
        ' Get the information out of the new file and display it.
        sr = New StreamReader(newfi.OpenRead())
        Console.WriteLine("{0}This is the information in the second file:", Environment.NewLine)
        While sr.Peek() <> -1
            Console.WriteLine(sr.ReadLine())
        End While
    End Sub
End Class
'This code produces output similar to the following; 
'results may vary based on the computer/file structure/etc.:
'
'This is the information in the first file:
'Add as many lines as you like...
'Add another line to the output...
'
'This is the information in the second file:
'Add as many lines as you like...
'Add another line to the output...
'

備註

使用這個方法來允許或防止覆寫現有的檔案。 CopyTo(String)使用方法來防止預設覆寫現有的檔案。

警告

請盡可能避免使用簡短檔名 (，例如XXXXXX~1.XXX) 此方法。 如果兩個檔案具有相等的簡短檔名，則此方法可能會失敗並引發例外狀況和/或導致不想要的行為

另請參閱

• 檔案和資料流 I/O
• 作法：讀取檔案中的文字
• 作法：將文字寫入檔案
• 作法：讀取和寫入新建立的資料檔案