Opens the file selected by the user, with read-only permission. The file is specified by the FileName property.
Namespace:
System.Windows.Forms
Assembly:
System.Windows.Forms (in System.Windows.Forms.dll)
Visual Basic (Declaration)
Public Function OpenFile As Stream
Dim instance As OpenFileDialog
Dim returnValue As Stream
returnValue = instance.OpenFile()
public:
Stream^ OpenFile()
public function OpenFile() : Stream
| Exception | Condition |
|---|
| ArgumentNullException | The file name is nullNothingnullptra null reference (Nothing in Visual Basic). |
The OpenFile method is used to provide a facility to quickly open a file from the dialog box. The file is opened in read-only mode for security purposes. To open a file in read/write mode, you must use another method, such as FileStream.
The following code example demonstrates how to use the OpenFile method.
Private Sub button1_Click(ByVal sender As Object, ByVal e As System.EventArgs)
Dim myStream As Stream = Nothing
Dim openFileDialog1 As New OpenFileDialog()
openFileDialog1.InitialDirectory = "c:\"
openFileDialog1.Filter = "txt files (*.txt)|*.txt|All files (*.*)|*.*"
openFileDialog1.FilterIndex = 2
openFileDialog1.RestoreDirectory = True
If openFileDialog1.ShowDialog() = System.Windows.Forms.DialogResult.OK Then
Try
myStream = openFileDialog1.OpenFile()
If (myStream IsNot Nothing) Then
' Insert code to read the stream here.
End If
Catch Ex As Exception
MessageBox.Show("Cannot read file from disk. Original error: " & Ex.Message)
Finally
' Check this again, since we need to make sure we didn't throw an exception on open.
If (myStream IsNot Nothing) Then
myStream.Close()
End If
End Try
End If
End Sub
private void button1_Click(object sender, System.EventArgs e)
{
Stream myStream = null;
OpenFileDialog openFileDialog1 = new OpenFileDialog();
openFileDialog1.InitialDirectory = "c:\\" ;
openFileDialog1.Filter = "txt files (*.txt)|*.txt|All files (*.*)|*.*" ;
openFileDialog1.FilterIndex = 2 ;
openFileDialog1.RestoreDirectory = true ;
if(openFileDialog1.ShowDialog() == DialogResult.OK)
{
try
{
if ((myStream = openFileDialog1.OpenFile()) != null)
{
using (myStream)
{
// Insert code to read the stream here.
}
}
}
catch (Exception ex)
{
MessageBox.Show("Error: Could not read file from disk. Original error: " + ex.Message);
}
}
}
private:
void button1_Click( Object^ /*sender*/, System::EventArgs^ /*e*/ )
{
Stream^ myStream;
OpenFileDialog^ openFileDialog1 = gcnew OpenFileDialog;
openFileDialog1->InitialDirectory = "c:\\";
openFileDialog1->Filter = "txt files (*.txt)|*.txt|All files (*.*)|*.*";
openFileDialog1->FilterIndex = 2;
openFileDialog1->RestoreDirectory = true;
if ( openFileDialog1->ShowDialog() == System::Windows::Forms::DialogResult::OK )
{
if ( (myStream = openFileDialog1->OpenFile()) != nullptr )
{
// Insert code to read the stream here.
myStream->Close();
}
}
}
Windows 7, Windows Vista, Windows XP SP2, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP Starter Edition, Windows Server 2008 R2, Windows Server 2008, Windows Server 2003, Windows Server 2000 SP4, Windows Millennium Edition, Windows 98
The .NET Framework and .NET Compact Framework do not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.
.NET Framework
Supported in: 3.5, 3.0, 2.0, 1.1, 1.0
Reference