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IsolatedStorageFile.FileExists Method

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

Determines whether the specified path refers to an existing file in the isolated store.

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

Syntax

'Declaration
<SecuritySafeCriticalAttribute> _
Public Function FileExists ( _
    path As String _
) As Boolean

[SecuritySafeCriticalAttribute]
public bool FileExists(
    string path
)

Parameters

Return Value

Type: System.Boolean
true if path refers to an existing file in the isolated store and is not nulla null reference (Nothing in Visual Basic); otherwise, false.

Exceptions

Exception Condition
IsolatedStorageException

The isolated store has been removed.

-or-

Isolated storage is disabled.
ObjectDisposedException

The isolated store has been disposed.

Examples

The following example determines whether a file exists before writing to it. This example is part of a larger example provided for IsolatedStorageFile class.

' Write to an existing file: MyApp1\SubDir1\MyApp1A.txt

' Determine if the file exists before writing to it.
Dim filePath As String = Path.Combine(subdirectory1, "MyApp1A.txt")

If store.FileExists(filePath) Then
    Try
        Using sw As StreamWriter = _
            New StreamWriter(store.OpenFile(filePath, FileMode.Open, FileAccess.Write))

            sw.WriteLine("To do list:")
            sw.WriteLine("1. Buy supplies.")
        End Using

    Catch ex As IsolatedStorageException
        sb.AppendLine(ex.Message)
    End Try
Else
    sb.AppendLine((filePath + "does not exist"))
End If

// Write to an existing file: MyApp1\SubDir1\MyApp1A.txt

// Determine if the file exists before writing to it.
string filePath = Path.Combine(subdirectory1, "MyApp1A.txt");

if (store.FileExists(filePath))
{
    try
    {
        using (StreamWriter sw =
            new StreamWriter(store.OpenFile(filePath,
                FileMode.Open, FileAccess.Write)))
        {
            sw.WriteLine("To do list:");
            sw.WriteLine("1. Buy supplies.");
        }
    }
    catch (IsolatedStorageException ex)
    {

        sb.AppendLine(ex.Message);
    }
}

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.