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File.Copy Method (String, String, Boolean)

When it is called by trusted applications, copies an existing file to a new file. Overwriting a file of the same name is allowed.

Namespace:  System.IO
Assembly:  mscorlib (in mscorlib.dll)

public static void Copy(
	string sourceFileName,
	string destFileName,
	bool overwrite


Type: System.String
The file to copy.
Type: System.String
The name of the destination file. This cannot be a directory.
Type: System.Boolean
true if the destination file can be overwritten; otherwise, false.


The caller does not have the required permission.


sourceFileName or destFileName is a zero-length string, contains only white space, or contains one or more invalid characters as defined by GetInvalidPathChars.


sourceFileName or destFileName specifies a directory.


sourceFileName or destFileName is null.


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.


The path specified in sourceFileName or destFileName is invalid (for example, it is on an unmapped drive).


sourceFileName was not found.


destFileName is read-only, or destFileName exists and overwrite is false.


An I/O error has occurred.


sourceFileName or destFileName is in an invalid format.

For more information about trusted applications, see Trusted Applications.

Platform Notes

Silverlight for Windows Phone Silverlight for Windows Phone

 This member has a SecurityCriticalAttribute attribute on Silverlight for Windows Phone, because the attribute was present in Silverlight 3. This attribute restricts this member to internal use. Application code that uses this member throws a MethodAccessException.


Supported in: 5, 4, 3

Silverlight for Windows Phone

Supported in: Windows Phone OS 7.1, Windows Phone OS 7.0

XNA Framework

Supported in: Xbox 360, Windows Phone OS 7.0

For a list of the operating systems and browsers that are supported by Silverlight, see Supported Operating Systems and Browsers.

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