FileInfo.CopyTo 方法

定義

命名空間:: System.IO

組件:: mscorlib.dll, System.IO.FileSystem.dll

組件:: netstandard.dll, System.Runtime.dll

組件:: netstandard.dll, System.IO.FileSystem.dll

組件:: netstandard.dll, System.IO.FileSystem.dll, System.Runtime.dll

組件:: System.IO.FileSystem.dll

組件:: mscorlib.dll

組件:: netstandard.dll

重要

部分資訊涉及發行前產品，在發行之前可能會有大幅修改。 Microsoft 對此處提供的資訊，不做任何明確或隱含的瑕疵擔保。

將現有的檔案複製到新的檔案。

多載

名稱	Description
CopyTo(String)	將現有的檔案複製到新的檔案，不允許覆寫現有的檔案。
CopyTo(String, Boolean)	將現有的檔案複製到新的檔案，允許覆寫現有的檔案。

CopyTo(String)

來源:: FileInfo.cs

來源:: FileInfo.cs

來源:: FileInfo.cs

來源:: FileInfo.cs

來源:: FileInfo.cs

將現有的檔案複製到新的檔案，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

要複製的新檔案名稱。

傳回

FileInfo

一個帶有完整限定路徑的新檔案。

例外狀況

ArgumentException

.NET Framework 及 2.1 .NET Core 版本：destFileName 為空、僅有空白或無效字元。

IOException

發生錯誤，或目標檔案已經存在。

SecurityException

來電者沒有所需的權限。

ArgumentNullException

destFileName 是 null。

UnauthorizedAccessException

會傳遞目錄路徑，或是檔案被移到另一個磁碟。

DirectoryNotFoundException

該 destFileName 目錄不存在。

PathTooLongException

指定的路徑、檔名或兩者都超過系統定義的最大長度。

NotSupportedException

destFileName 字串中包含冒號（:)，但未指定音量。

範例

以下範例展示了該 CopyTo 方法的兩種過載。

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

以下範例示範將一個檔案複製到另一個檔案，若目標檔案已存在則拋出例外。

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

使用此 CopyTo(String, Boolean) 方法允許覆蓋現有檔案。

注意事項

盡可能避免使用此方法使用短檔名（例如 XXXXXX~1.XXX）。若兩個檔案的短檔名稱相同，此方法可能會失敗並觸發例外及/或造成不良行為

另請參閱

適用於

CopyTo(String, Boolean)

來源:: FileInfo.cs

來源:: FileInfo.cs

來源:: FileInfo.cs

來源:: FileInfo.cs

來源:: FileInfo.cs

將現有的檔案複製到新的檔案，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