FileInfo
FileInfo
FileInfo
FileInfo
Class
Definition
Provides properties and instance methods for the creation, copying, deletion, moving, and opening of files, and aids in the creation of FileStream objects. This class cannot be inherited.
public ref class FileInfo sealed : System::IO::FileSystemInfo
[System.Runtime.InteropServices.ComVisible(true)]
[System.Serializable]
public sealed class FileInfo : System.IO.FileSystemInfo
type FileInfo = class
inherit FileSystemInfo
Public NotInheritable Class FileInfo
Inherits FileSystemInfo
- Inheritance
- Attributes
Examples
The following example demonstrates some of the main members of the FileInfo class.
When the properties are first retrieved, FileInfo calls the Refresh method and caches information about the file. On subsequent calls, you must call Refresh to get the latest copy of the information.
using namespace System;
using namespace System::IO;
int main()
{
String^ path = Path::GetTempFileName();
FileInfo^ fi1 = gcnew FileInfo( path );
//Create a file to write to.
StreamWriter^ sw = fi1->CreateText();
try
{
sw->WriteLine( "Hello" );
sw->WriteLine( "And" );
sw->WriteLine( "Welcome" );
}
finally
{
if ( sw )
delete (IDisposable^)sw;
}
//Open the file to read from.
StreamReader^ sr = fi1->OpenText();
try
{
String^ s = "";
while ( s = sr->ReadLine() )
{
Console::WriteLine( s );
}
}
finally
{
if ( sr )
delete (IDisposable^)sr;
}
try
{
String^ path2 = Path::GetTempFileName();
FileInfo^ fi2 = gcnew FileInfo( path2 );
//Ensure that the target does not exist.
fi2->Delete();
//Copy the file.
fi1->CopyTo( path2 );
Console::WriteLine( "{0} was copied to {1}.", path, path2 );
//Delete the newly created file.
fi2->Delete();
Console::WriteLine( "{0} was successfully deleted.", path2 );
}
catch ( Exception^ e )
{
Console::WriteLine( "The process failed: {0}", e );
}
}
using System;
using System.IO;
class Test
{
public static void Main()
{
string path = Path.GetTempFileName();
FileInfo fi1 = new FileInfo(path);
//Create a file to write to.
using (StreamWriter sw = fi1.CreateText())
{
sw.WriteLine("Hello");
sw.WriteLine("And");
sw.WriteLine("Welcome");
}
//Open the file to read from.
using (StreamReader sr = fi1.OpenText())
{
string s = "";
while ((s = sr.ReadLine()) != null)
{
Console.WriteLine(s);
}
}
try
{
string path2 = Path.GetTempFileName();
FileInfo fi2 = new FileInfo(path2);
//Ensure that the target does not exist.
fi2.Delete();
//Copy the file.
fi1.CopyTo(path2);
Console.WriteLine("{0} was copied to {1}.", path, path2);
//Delete the newly created file.
fi2.Delete();
Console.WriteLine("{0} was successfully deleted.", path2);
}
catch (Exception e)
{
Console.WriteLine("The process failed: {0}", e.ToString());
}
}
}
Imports System
Imports System.IO
Public Class Test
Public Shared Sub Main()
Dim path1 As String = Path.GetTempFileName()
Dim path2 As String = Path.GetTempFileName()
Dim fi As FileInfo = New FileInfo(path1)
'Create a file to write to.
Dim sw As StreamWriter = fi.CreateText()
sw.WriteLine("Hello")
sw.WriteLine("And")
sw.WriteLine("Welcome")
sw.Flush()
sw.Close()
Try
'Open the file to read from.
Dim sr As StreamReader = fi.OpenText()
Do While sr.Peek() >= 0
Console.WriteLine(sr.ReadLine())
Loop
sr.Close()
Dim fi2 As FileInfo = New FileInfo(path2)
'Ensure that the target does not exist.
fi2.Delete()
'Copy the file.
fi.CopyTo(path2)
Console.WriteLine("{0} was copied to {1}.", path1, path2)
'Delete the newly created file.
fi2.Delete()
Console.WriteLine("{0} was successfully deleted.", path2)
Catch e As Exception
Console.WriteLine("The process failed: {0}.", e.ToString())
End Try
End Sub
End Class
This example produces output similar to the following.
Hello
And
Welcome
C:\Users\userName\AppData\Local\Temp\tmp70AB.tmp was copied to C:\Users\userName\AppData\Local\Temp\tmp70CB.tmp.
C:\Users\userName\AppData\Local\Temp\tmp70CB.tmp was successfully deleted.
Remarks
Use the FileInfo class for typical operations such as copying, moving, renaming, creating, opening, deleting, and appending to files.
If you are performing multiple operations on the same file, it can be more efficient to use FileInfo instance methods instead of the corresponding static methods of the File class, because a security check will not always be necessary.
Many of the FileInfo methods return other I/O types when you create or open files. You can use these other types to further manipulate a file. For more information, see specific FileInfo members such as Open, OpenRead, OpenText, CreateText, or Create.
By default, full read/write access to new files is granted to all users.
The following table describes the enumerations that are used to customize the behavior of various FileInfo methods.
| Enumeration | Description |
|---|---|
| FileAccess | Specifies read and write access to a file. |
| FileShare | Specifies the level of access permitted for a file that is already in use. |
| FileMode | Specifies whether the contents of an existing file are preserved or overwritten, and whether requests to create an existing file cause an exception. |
Note
In members that accept a path as an input string, that path must be well-formed or an exception is raised. For example, if a path is fully qualified but begins with a space, the path is not trimmed in methods of the class. Therefore, the path is malformed and an exception is raised. Similarly, a path or a combination of paths cannot be fully qualified twice. For example, "c:\temp c:\windows" also raises an exception in most cases. Ensure that your paths are well-formed when using methods that accept a path string.
In members that accept a path, the path can refer to a file or just a directory. The specified path can also refer to a relative path or a Universal Naming Convention (UNC) path for a server and share name. For example, all the following are acceptable paths:
"c:\\MyDir\\MyFile.txt" in C#, or "c:\MyDir\MyFile.txt" in Visual Basic.
"c:\\MyDir" in C#, or "c:\MyDir" in Visual Basic.
"MyDir\\MySubdir" in C#, or "MyDir\MySubDir" in Visual Basic.
"\\\\MyServer\\MyShare" in C#, or "\\MyServer\MyShare" in Visual Basic.
The FileInfo class provides the following properties that enable you to retrieve information about a file. For an example of how to use each property, see the property pages.
The Directory property retrieves an object that represents the parent directory of a file.
The DirectoryName property retrieves the full path of the parent directory of a file.
The Exists property checks for the presence of a file before operating on it.
The IsReadOnly property retrieves or sets a value that specifies whether a file can be modified.
The Length retrieves the size of a file.
The Name retrieves the name of a file.
Constructors
| FileInfo(String) FileInfo(String) FileInfo(String) FileInfo(String) |
Initializes a new instance of the FileInfo class, which acts as a wrapper for a file path. |
Properties
| Attributes Attributes Attributes Attributes |
Gets or sets the attributes for the current file or directory. (Inherited from FileSystemInfo) |
| CreationTime CreationTime CreationTime CreationTime |
Gets or sets the creation time of the current file or directory. (Inherited from FileSystemInfo) |
| CreationTimeUtc CreationTimeUtc CreationTimeUtc CreationTimeUtc |
Gets or sets the creation time, in coordinated universal time (UTC), of the current file or directory. (Inherited from FileSystemInfo) |
| Directory Directory Directory Directory |
Gets an instance of the parent directory. |
| DirectoryName DirectoryName DirectoryName DirectoryName |
Gets a string representing the directory's full path. |
| Exists Exists Exists Exists |
Gets a value indicating whether a file exists. |
| Extension Extension Extension Extension |
Gets the string representing the extension part of the file. (Inherited from FileSystemInfo) |
| FullName FullName FullName FullName |
Gets the full path of the directory or file. (Inherited from FileSystemInfo) |
| IsReadOnly IsReadOnly IsReadOnly IsReadOnly |
Gets or sets a value that determines if the current file is read only. |
| LastAccessTime LastAccessTime LastAccessTime LastAccessTime |
Gets or sets the time the current file or directory was last accessed. (Inherited from FileSystemInfo) |
| LastAccessTimeUtc LastAccessTimeUtc LastAccessTimeUtc LastAccessTimeUtc |
Gets or sets the time, in coordinated universal time (UTC), that the current file or directory was last accessed. (Inherited from FileSystemInfo) |
| LastWriteTime LastWriteTime LastWriteTime LastWriteTime |
Gets or sets the time when the current file or directory was last written to. (Inherited from FileSystemInfo) |
| LastWriteTimeUtc LastWriteTimeUtc LastWriteTimeUtc LastWriteTimeUtc |
Gets or sets the time, in coordinated universal time (UTC), when the current file or directory was last written to. (Inherited from FileSystemInfo) |
| Length Length Length Length |
Gets the size, in bytes, of the current file. |
| Name Name Name Name |
Gets the name of the file. |
Methods
Fields
| FullPath FullPath FullPath FullPath |
Represents the fully qualified path of the directory or file. (Inherited from FileSystemInfo) |
| OriginalPath OriginalPath OriginalPath OriginalPath |
The path originally specified by the user, whether relative or absolute. (Inherited from FileSystemInfo) |