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Image.FromFile Method

Definition

Creates an Image from the specified file.

Overloads

FromFile(String)

Creates an Image from the specified file.

FromFile(String, Boolean)

Creates an Image from the specified file using embedded color management information in that file.

FromFile(String)

Source:
Image.cs
Source:
Image.cs
Source:
Image.cs
Source:
Image.cs
Source:
Image.cs

Creates an Image from the specified file.

public:
 static System::Drawing::Image ^ FromFile(System::String ^ filename);
public static System.Drawing.Image FromFile (string filename);
static member FromFile : string -> System.Drawing.Image
Public Shared Function FromFile (filename As String) As Image

Parameters

filename
String

A string that contains the name of the file from which to create the Image.

Returns

The Image this method creates.

Exceptions

The file does not have a valid image format.

-or-

GDI+ does not support the pixel format of the file.

The specified file does not exist.

filename is a Uri.

Examples

The following code example demonstrates how to use the FromFileGetPropertyItem and SetPropertyItem methods. This example is designed to be used with Windows Forms. To run this example, paste it into a form, and handle the form's Paint event by calling the DemonstratePropertyItem method, passing e as PaintEventArgs.

private:
   void DemonstratePropertyItem( PaintEventArgs^ e )
   {
      // Create two images.
      Image^ image1 = Image::FromFile( "c:\\FakePhoto1.jpg" );
      Image^ image2 = Image::FromFile( "c:\\FakePhoto2.jpg" );

      // Get a PropertyItem from image1.
      PropertyItem^ propItem = image1->GetPropertyItem( 20624 );

      // Change the ID of the PropertyItem.
      propItem->Id = 20625;

      // Set the PropertyItem for image2.
      image2->SetPropertyItem( propItem );

      // Draw the image.
      e->Graphics->DrawImage( image2, 20.0F, 20.0F );
   }
private void DemonstratePropertyItem(PaintEventArgs e)
{

    // Create two images.
    Image image1 = Image.FromFile("c:\\FakePhoto1.jpg");
    Image image2 = Image.FromFile("c:\\FakePhoto2.jpg");

    // Get a PropertyItem from image1.
    PropertyItem propItem = image1.GetPropertyItem(20624);

    // Change the ID of the PropertyItem.
    propItem.Id = 20625;

    // Set the PropertyItem for image2.
    image2.SetPropertyItem(propItem);

    // Draw the image.
    e.Graphics.DrawImage(image2, 20.0F, 20.0F);
}
Private Sub DemonstratePropertyItem(ByVal e As PaintEventArgs)

    ' Create two images.
    Dim image1 As Image = Image.FromFile("c:\FakePhoto1.jpg")
    Dim image2 As Image = Image.FromFile("c:\FakePhoto2.jpg")

    ' Get a PropertyItem from image1.
    Dim propItem As PropertyItem = image1.GetPropertyItem(20624)

    ' Change the ID of the PropertyItem.
    propItem.Id = 20625

    ' Set the PropertyItem for image2.
    image2.SetPropertyItem(propItem)

    ' Draw the image.
    e.Graphics.DrawImage(image2, 20.0F, 20.0F)
End Sub

Remarks

Managed GDI+ has built-in encoders and decoders that support the following file types:

  • BMP

  • GIF

  • JPEG

  • PNG

  • TIFF

The file remains locked until the Image is disposed.

If the file does not have a valid image format or if GDI+ does not support the pixel format of the file, this method throws an OutOfMemoryException exception.

Note

The Image class does not support alpha transparency in bitmaps. To enable alpha transparency, use PNG images with 32 bits per pixel.

See also

Applies to

FromFile(String, Boolean)

Source:
Image.cs
Source:
Image.cs
Source:
Image.cs
Source:
Image.cs
Source:
Image.cs

Creates an Image from the specified file using embedded color management information in that file.

public:
 static System::Drawing::Image ^ FromFile(System::String ^ filename, bool useEmbeddedColorManagement);
public static System.Drawing.Image FromFile (string filename, bool useEmbeddedColorManagement);
static member FromFile : string * bool -> System.Drawing.Image
Public Shared Function FromFile (filename As String, useEmbeddedColorManagement As Boolean) As Image

Parameters

filename
String

A string that contains the name of the file from which to create the Image.

useEmbeddedColorManagement
Boolean

Set to true to use color management information embedded in the image file; otherwise, false.

Returns

The Image this method creates.

Exceptions

The file does not have a valid image format.

-or-

GDI+ does not support the pixel format of the file.

The specified file does not exist.

filename is a Uri.

Examples

The following code example demonstrates how to obtain a new bitmap using the FromFile method. It also demonstrates a TextureBrush.

This example is designed to be used with Windows Forms. Create a form containing a button named Button2. Paste the code into the form and associate the Button2_Click method with the button's Click event.

private:
   void Button2_Click( System::Object^ /*sender*/, System::EventArgs^ /*e*/ )
   {
      try
      {
         Bitmap^ image1 = dynamic_cast<Bitmap^>(Image::FromFile( "C:\\Documents and Settings\\"
         "All Users\\Documents\\My Music\\music.bmp", true ));
         TextureBrush^ texture = gcnew TextureBrush( image1 );
         texture->WrapMode = System::Drawing::Drawing2D::WrapMode::Tile;
         Graphics^ formGraphics = this->CreateGraphics();
         formGraphics->FillEllipse( texture, RectangleF(90.0F,110.0F,100,100) );
         delete formGraphics;
      }
      catch ( System::IO::FileNotFoundException^ ) 
      {
         MessageBox::Show( "There was an error opening the bitmap."
         "Please check the path." );
      }
   }
private void Button2_Click(System.Object sender, System.EventArgs e)
{
    try
    {
        Bitmap image1 = (Bitmap) Image.FromFile(@"C:\Documents and Settings\" +
            @"All Users\Documents\My Music\music.bmp", true);

        TextureBrush texture = new TextureBrush(image1);
        texture.WrapMode = System.Drawing.Drawing2D.WrapMode.Tile;
        Graphics formGraphics = this.CreateGraphics();
        formGraphics.FillEllipse(texture, 
            new RectangleF(90.0F, 110.0F, 100, 100));
        formGraphics.Dispose();
    }
    catch(System.IO.FileNotFoundException)
    {
        MessageBox.Show("There was an error opening the bitmap." +
            "Please check the path.");
    }
}
Private Sub Button2_Click(ByVal sender As System.Object, _
    ByVal e As System.EventArgs) Handles Button2.Click
    Try
        Dim image1 As Bitmap = _
            CType(Image.FromFile("C:\Documents and Settings\" _
            & "All Users\Documents\My Music\music.bmp", True), Bitmap)

        Dim texture As New TextureBrush(image1)
        texture.WrapMode = Drawing2D.WrapMode.Tile
        Dim formGraphics As Graphics = Me.CreateGraphics()
        formGraphics.FillEllipse(texture, _
            New RectangleF(90.0F, 110.0F, 100, 100))
        formGraphics.Dispose()

    Catch ex As System.IO.FileNotFoundException
        MessageBox.Show("There was an error opening the bitmap." _
            & "Please check the path.")
    End Try

End Sub

Remarks

Managed GDI+ has built-in encoders and decoders that support the following file types:

  • BMP

  • GIF

  • JPEG

  • PNG

  • TIFF

If the file does not have a valid image format or if GDI+ does not support the pixel format of the file, this method throws an OutOfMemoryException exception.

The file remains locked until the Image is disposed.

The useEmbeddedColorManagement parameter specifies whether the new Image applies color correction according to color management information that is embedded in the image file. Embedded information can include International Color Consortium (ICC) profiles, gamma values, and chromaticity information.

Note

The Image class does not support alpha transparency in bitmaps. To enable alpha transparency, use PNG images with 32 bits per pixel.

See also

Applies to