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FileInfo::CopyTo Method (String)

Copies an existing file to a new file, disallowing the overwriting of an existing file.

Namespace:  System.IO
Assembly:  mscorlib (in mscorlib.dll)
public:
FileInfo^ CopyTo(
	String^ destFileName
)

Parameters

destFileName
Type: System::String

The name of the new file to copy to.

Return Value

Type: System.IO::FileInfo
A new file with a fully qualified path.
ExceptionCondition
ArgumentException

destFileName is empty, contains only white spaces, or contains invalid characters.

IOException

An error occurs, or the destination file already exists.

SecurityException

The caller does not have the required permission.

ArgumentNullException

destFileName is nullptr.

UnauthorizedAccessException

A directory path is passed in, or the file is being moved to a different drive.

DirectoryNotFoundException

The directory specified in destFileName does not exist.

PathTooLongException

The specified path, file name, or both exceed the system-defined maximum length. For example, on Windows-based platforms, paths must be less than 248 characters, and file names must be less than 260 characters.

NotSupportedException

destFileName contains a colon (:) within the string but does not specify the volume.

Use the CopyTo method to allow overwriting of an existing file.

Caution noteCaution

Whenever possible, avoid using short file names (such as XXXXXX~1.XXX) with this method. If two files have equivalent short file names then this method may fail and raise an exception and/or result in undesirable behavior

The following example demonstrates both overloads of the CopyTo method.

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.

The following example demonstrates copying one file to another file, throwing an exception if the destination file already exists.

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:

.NET Framework

Supported in: 4.5.1, 4.5, 4, 3.5, 3.0, 2.0, 1.1, 1.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

.NET for Windows Phone apps

Supported in: Windows Phone 8.1, Windows Phone 8, Silverlight 8.1

Windows Phone 8.1, Windows Phone 8, Windows 8.1, Windows Server 2012 R2, Windows 8, Windows Server 2012, Windows 7, Windows Vista SP2, Windows Server 2008 (Server Core Role not supported), Windows Server 2008 R2 (Server Core Role supported with SP1 or later; Itanium not supported)

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

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