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FileInfo Class

Microsoft Silverlight will reach end of support after October 2021. Learn more.

Provides 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.

Inheritance Hierarchy

System.Object
  System.IO.FileSystemInfo
    System.IO.FileInfo

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

Syntax

'Declaration
<ComVisibleAttribute(True)> _
Public NotInheritable Class FileInfo _
    Inherits FileSystemInfo
[ComVisibleAttribute(true)]
public sealed class FileInfo : FileSystemInfo

The FileInfo type exposes the following members.

Constructors

  Name Description
Public methodSupported by Silverlight for Windows PhoneSupported by Xbox 360 FileInfo When it is called by trusted applications, initializes a new instance of the FileInfo class, which acts as a wrapper for a file path.

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Properties

  Name Description
Public propertySupported by Silverlight for Windows PhoneSupported by Xbox 360 Attributes When called by trusted applications, gets or sets the FileAttributes of the current FileSystemInfo. (Inherited from FileSystemInfo.)
Public propertySupported by Silverlight for Windows PhoneSupported by Xbox 360 CreationTime When called by trusted applications, gets or sets the creation time of the current FileSystemInfo object. (Inherited from FileSystemInfo.)
Public propertySupported by Silverlight for Windows PhoneSupported by Xbox 360 Directory When it is called by trusted applications, gets an instance of the parent directory.
Public propertySupported by Silverlight for Windows PhoneSupported by Xbox 360 DirectoryName When it is called by trusted applications, gets a string representing the directory's full path.
Public propertySupported by Silverlight for Windows PhoneSupported by Xbox 360 Exists Gets a value indicating whether a file exists. (Overrides FileSystemInfo.Exists.)
Public propertySupported by Silverlight for Windows PhoneSupported by Xbox 360 Extension Gets the string representing the extension part of the file. (Inherited from FileSystemInfo.)
Public propertySupported by Silverlight for Windows PhoneSupported by Xbox 360 FullName When called by trusted applications, gets the full path of the directory or file. (Inherited from FileSystemInfo.)
Public propertySupported by Silverlight for Windows PhoneSupported by Xbox 360 LastAccessTime When called by trusted applications, gets or sets the time the current file or directory was last accessed. (Inherited from FileSystemInfo.)
Public propertySupported by Silverlight for Windows PhoneSupported by Xbox 360 LastWriteTime When called by trusted applications, gets or sets the time when the current file or directory was last written to. (Inherited from FileSystemInfo.)
Public propertySupported by Silverlight for Windows PhoneSupported by Xbox 360 Length Gets the size, in bytes, of the current file.
Public propertySupported by Silverlight for Windows PhoneSupported by Xbox 360 Name Gets the name of the file. (Overrides FileSystemInfo.Name.)

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Methods

  Name Description
Public methodSupported by Silverlight for Windows PhoneSupported by Xbox 360 AppendText When it is called by trusted applications, creates a StreamWriter that appends text to the file represented by this instance of the FileInfo.
Public methodSupported by Silverlight for Windows PhoneSupported by Xbox 360 CopyTo(String) When it is called by trusted applications, copies an existing file to a new file, disallowing the overwriting of an existing file.
Public methodSupported by Silverlight for Windows PhoneSupported by Xbox 360 CopyTo(String, Boolean) When it is called by trusted applications, copies an existing file to a new file, allowing the overwriting of an existing file.
Public methodSupported by Silverlight for Windows PhoneSupported by Xbox 360 Create When it is called by trusted applications, creates a file.
Public methodSupported by Silverlight for Windows PhoneSupported by Xbox 360 CreateText When it is called by trusted applications, creates a StreamWriter that writes a new text file.
Public methodSupported by Silverlight for Windows PhoneSupported by Xbox 360 Delete When it is called by trusted applications, permanently deletes a file. (Overrides FileSystemInfo.Delete().)
Public methodSupported by Silverlight for Windows PhoneSupported by Xbox 360 Equals(Object) Determines whether the specified Object is equal to the current Object. (Inherited from Object.)
Protected methodSupported by Silverlight for Windows PhoneSupported by Xbox 360 Finalize Allows an object to try to free resources and perform other cleanup operations before the Object is reclaimed by garbage collection. (Inherited from Object.)
Public methodSupported by Silverlight for Windows PhoneSupported by Xbox 360 GetHashCode Serves as a hash function for a particular type. (Inherited from Object.)
Public methodSupported by Silverlight for Windows PhoneSupported by Xbox 360 GetType Gets the Type of the current instance. (Inherited from Object.)
Protected methodSupported by Silverlight for Windows PhoneSupported by Xbox 360 MemberwiseClone Creates a shallow copy of the current Object. (Inherited from Object.)
Public methodSupported by Silverlight for Windows PhoneSupported by Xbox 360 MoveTo When it is called by trusted applications, moves a specified file to a new location, providing the option to specify a new file name.
Public methodSupported by Silverlight for Windows PhoneSupported by Xbox 360 Open(FileMode) When it is called by trusted applications, opens a file in the specified mode.
Public methodSupported by Silverlight for Windows PhoneSupported by Xbox 360 Open(FileMode, FileAccess) When it is called by trusted applications, opens a file in the specified mode with read, write, or read/write access.
Public methodSupported by Silverlight for Windows PhoneSupported by Xbox 360 Open(FileMode, FileAccess, FileShare) When it is called by trusted applications, opens a file in the specified mode with read, write, or read/write access and the specified sharing option.
Public methodSupported by Silverlight for Windows PhoneSupported by Xbox 360 OpenRead Creates a read-only FileStream.
Public methodSupported by Silverlight for Windows PhoneSupported by Xbox 360 OpenText Creates a StreamReader with UTF8 encoding that reads from an existing text file.
Public methodSupported by Silverlight for Windows PhoneSupported by Xbox 360 OpenWrite When it is called by trusted applications, creates a write-only FileStream.
Public methodSupported by Silverlight for Windows PhoneSupported by Xbox 360 Refresh Refreshes the state of the object. (Inherited from FileSystemInfo.)
Public methodSupported by Silverlight for Windows PhoneSupported by Xbox 360 ToString Returns the path as a string. (Overrides Object.ToString().)

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Fields

  Name Description
Protected fieldSupported by Silverlight for Windows PhoneSupported by Xbox 360 FullPath Infrastructure. Represents the fully qualified path of the directory or file. (Inherited from FileSystemInfo.)
Protected fieldSupported by Silverlight for Windows PhoneSupported by Xbox 360 OriginalPath Infrastructure. The path originally specified by the user, whether relative or absolute. (Inherited from FileSystemInfo.)

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Examples

The following example displays an image picked at random from the user's My Pictures folder. It uses the DirectoryInfo class to obtain an enumerable collection of FileInfo objects that represent files that have a .jpg or .png extension. That collection is used to construct a List<T> collection so that its index can be used to select a file that corresponds to the random number.

The example then creates a bitmap image by using the FileStream class and sets it as the source for an Image control (named myImage).

For example code and information about how to create an application that runs outside the browser, see Out-of-Browser Support.

Private Sub LoadImage()

    If Application.Current.HasElevatedPermissions Then
        Dim di As New DirectoryInfo(Environment.GetFolderPath(Environment.SpecialFolder.MyPictures))

        Dim files = From f In di.EnumerateFiles() _
            Where f.Extension.ToLower() = ".jpg" OrElse f.Extension = ".png" _
            Select f

        Dim max As Integer = files.Count() + 1

        Dim rnd As New Random()
        Dim r As Integer = rnd.[Next](0, max)

        Dim pics As New List(Of FileInfo)(files)

        Dim randpic As String = pics(r).FullName

        Dim img As New BitmapImage()
        img.SetSource(New FileStream(randpic, FileMode.Open))


        MyImage.Source = img
    End If
End Sub
private void LoadImage()
{

    if (Application.Current.HasElevatedPermissions)
    {
        DirectoryInfo di = new DirectoryInfo(Environment.GetFolderPath(
           Environment.SpecialFolder.MyPictures));

        var files = from f in di.EnumerateFiles()
                    where f.Extension.ToLower() == ".jpg" || 
                        f.Extension == ".png"
                    select f;

        int max = files.Count() + 1;

        Random rnd = new Random();
        int r = rnd.Next(0, max);

        List<FileInfo> pics = new List<FileInfo>(files);

        string randpic = pics[r].FullName;

        BitmapImage img = new BitmapImage();
        img.SetSource(new FileStream(randpic, FileMode.Open));

        MyImage.Source = img;

    }
}

Version Information

Silverlight

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

Platforms

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

Thread Safety

Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.