ImageLockMode ImageLockMode ImageLockMode ImageLockMode Enum

定義

LockBits メソッドのフラグ パラメーターに渡すフラグを指定します。 LockBits メソッドは、ピクセル データの読み取りや書き込みができるように、イメージの一部をロックします。The LockBits method locks a portion of an image so that you can read or write the pixel data.

public enum class ImageLockMode
public enum ImageLockMode
type ImageLockMode = 
Public Enum ImageLockMode
継承
ImageLockModeImageLockModeImageLockModeImageLockMode

フィールド

ReadOnly ReadOnly ReadOnly ReadOnly 1

読み取りのためにイメージの一部をロックすることを指定します。Specifies that a portion of the image is locked for reading.

ReadWrite ReadWrite ReadWrite ReadWrite 3

読み取りまたは書き込みのためにイメージの一部をロックすることを指定します。Specifies that a portion of the image is locked for reading or writing.

UserInputBuffer UserInputBuffer UserInputBuffer UserInputBuffer 4

ピクセル データの読み取りまたは書き込みに使用されるバッファーがユーザーにより割り当てられることを指定します。Specifies that the buffer used for reading or writing pixel data is allocated by the user. このフラグがセットされた場合、LockBits メソッドの flags パラメーターは入力パラメーターとして (可能な場合は出力パラメーターとしても) 使用されます。If this flag is set, the flags parameter of the LockBits method serves as an input parameter (and possibly as an output parameter). このフラグがクリアされた場合、flags パラメーターは出力パラメーターとしてだけ使用されます。If this flag is cleared, then the flags parameter serves only as an output parameter.

WriteOnly WriteOnly WriteOnly WriteOnly 2

書き込みのためにイメージの一部をロックすることを指定します。Specifies that a portion of the image is locked for writing.

次のコード例は、使用する方法を示します、 PixelFormatHeightWidth、およびScan0プロパティ、LockBitsUnlockBitsメソッドとImageLockMode列挙体。The following code example demonstrates how to use the PixelFormat, Height, Width, and Scan0 properties; the LockBits and UnlockBits methods; and the ImageLockMode enumeration. この例は、Windows フォームで使用する設計されています。This example is designed to be used with Windows Forms. この例を実行するフォームに貼り付けることと、フォームの処理Paintイベントを呼び出すことによって、LockUnlockBitsExampleを渡してメソッドeとしてPaintEventArgsします。To run this example, paste it into a form and handle the form's Paint event by calling the LockUnlockBitsExample method, passing e as PaintEventArgs.

void LockUnlockBitsExample( PaintEventArgs^ e )
{
   // Create a new bitmap.
   Bitmap^ bmp = gcnew Bitmap( "c:\\fakePhoto.jpg" );

   // Lock the bitmap's bits.  
   Rectangle rect = Rectangle(0,0,bmp->Width,bmp->Height);
   System::Drawing::Imaging::BitmapData^ bmpData = bmp->LockBits( rect, System::Drawing::Imaging::ImageLockMode::ReadWrite, bmp->PixelFormat );

   // Get the address of the first line.
   IntPtr ptr = bmpData->Scan0;

   // Declare an array to hold the bytes of the bitmap.
   // This code is specific to a bitmap with 24 bits per pixels.
   int bytes = Math::Abs(bmpData->Stride) * bmp->Height;
   array<Byte>^rgbValues = gcnew array<Byte>(bytes);

   // Copy the RGB values into the array.
   System::Runtime::InteropServices::Marshal::Copy( ptr, rgbValues, 0, bytes );

   // Set every third value to 255.  
   for ( int counter = 2; counter < rgbValues->Length; counter += 3 )
      rgbValues[ counter ] = 255;

   // Copy the RGB values back to the bitmap
   System::Runtime::InteropServices::Marshal::Copy( rgbValues, 0, ptr, bytes );

   // Unlock the bits.
   bmp->UnlockBits( bmpData );

   // Draw the modified image.
   e->Graphics->DrawImage( bmp, 0, 150 );
}
private void LockUnlockBitsExample(PaintEventArgs e)
    {

        // Create a new bitmap.
        Bitmap bmp = new Bitmap("c:\\fakePhoto.jpg");

        // Lock the bitmap's bits.  
        Rectangle rect = new Rectangle(0, 0, bmp.Width, bmp.Height);
        System.Drawing.Imaging.BitmapData bmpData =
            bmp.LockBits(rect, System.Drawing.Imaging.ImageLockMode.ReadWrite,
            bmp.PixelFormat);

        // Get the address of the first line.
        IntPtr ptr = bmpData.Scan0;

        // Declare an array to hold the bytes of the bitmap.
        int bytes  = Math.Abs(bmpData.Stride) * bmp.Height;
        byte[] rgbValues = new byte[bytes];

        // Copy the RGB values into the array.
        System.Runtime.InteropServices.Marshal.Copy(ptr, rgbValues, 0, bytes);

        // Set every third value to 255. A 24bpp bitmap will look red.  
        for (int counter = 2; counter < rgbValues.Length; counter += 3)
            rgbValues[counter] = 255;

        // Copy the RGB values back to the bitmap
        System.Runtime.InteropServices.Marshal.Copy(rgbValues, 0, ptr, bytes);

        // Unlock the bits.
        bmp.UnlockBits(bmpData);

        // Draw the modified image.
        e.Graphics.DrawImage(bmp, 0, 150);

    }

Private Sub LockUnlockBitsExample(ByVal e As PaintEventArgs)

    ' Create a new bitmap.
    Dim bmp As New Bitmap("c:\fakePhoto.jpg")

    ' Lock the bitmap's bits.  
    Dim rect As New Rectangle(0, 0, bmp.Width, bmp.Height)
    Dim bmpData As System.Drawing.Imaging.BitmapData = bmp.LockBits(rect, _
        Drawing.Imaging.ImageLockMode.ReadWrite, bmp.PixelFormat)

    ' Get the address of the first line.
    Dim ptr As IntPtr = bmpData.Scan0

    ' Declare an array to hold the bytes of the bitmap.
    ' This code is specific to a bitmap with 24 bits per pixels.
    Dim bytes As Integer = Math.Abs(bmpData.Stride) * bmp.Height
    Dim rgbValues(bytes - 1) As Byte

    ' Copy the RGB values into the array.
    System.Runtime.InteropServices.Marshal.Copy(ptr, rgbValues, 0, bytes)

    ' Set every third value to 255. A 24bpp image will look red.
    For counter As Integer = 2 To rgbValues.Length - 1 Step 3
        rgbValues(counter) = 255
    Next

    ' Copy the RGB values back to the bitmap
    System.Runtime.InteropServices.Marshal.Copy(rgbValues, 0, ptr, bytes)

    ' Unlock the bits.
    bmp.UnlockBits(bmpData)

    ' Draw the modified image.
    e.Graphics.DrawImage(bmp, 0, 150)

End Sub

適用対象