FileMode Enumeration
Microsoft Silverlight will reach end of support after October 2021. Learn more.
Specifies how the operating system should open a file.
Namespace: System.IO
Assembly: mscorlib (in mscorlib.dll)
Syntax
'Declaration
<ComVisibleAttribute(True)> _
Public Enumeration FileMode
[ComVisibleAttribute(true)]
public enum FileMode
Members
Member name | Description | |
---|---|---|
CreateNew | Specifies that the operating system should create a new file. | |
Create | Specifies that the operating system should create a new file. If the file already exists, it will be overwritten. Create is equivalent to requesting that if the file does not exist, use CreateNew; otherwise, use Truncate. | |
Open | Specifies that the operating system should open an existing file. The ability to open the file is dependent on the value specified by FileAccess. A System.IO.FileNotFoundException is thrown if the file does not exist. | |
OpenOrCreate | Specifies that the operating system should open a file if it exists; otherwise, a new file should be created. | |
Truncate | Specifies that the operating system should open an existing file. Once opened, the file should be truncated so that its size is zero bytes. | |
Append | Opens the file if it exists and seeks to the end of the file, or creates a new file. Append can only be used in conjunction with Write. Attempting to seek to a position before the end of the file will throw an IOException and any attempt to read fails and throws an NotSupportedException. |
Examples
The following example opens an existing file. This example is part of a larger example provided for the 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.