Bitmap.UnlockBits(BitmapData) Bitmap.UnlockBits(BitmapData) Bitmap.UnlockBits(BitmapData) Method

Определение

Разблокирует это изображение Bitmap из оперативной памяти.Unlocks this Bitmap from system memory.

public:
 void UnlockBits(System::Drawing::Imaging::BitmapData ^ bitmapdata);
public void UnlockBits (System.Drawing.Imaging.BitmapData bitmapdata);
member this.UnlockBits : System.Drawing.Imaging.BitmapData -> unit

Параметры

bitmapdata
BitmapData BitmapData BitmapData

Объект BitmapData, задающий сведения об этой операции блокировки.A BitmapData that specifies information about the lock operation.

Исключения

Операция выполнена со сбоем.The operation failed.

Примеры

В следующем примере кода демонстрируется использование PixelFormat, Height, Width, и Scan0 свойства; LockBits и UnlockBits методов; и ImageLockMode перечисления.The following code example demonstrates how to use the PixelFormat, Height, Width, and Scan0 properties; the LockBits and UnlockBits methods; and the ImageLockMode enumeration. Этот пример не предназначен для правильной работы со всеми форматами пикселей, но пример демонстрирует использование LockBits метод.This example is not designed to work correctly with all pixel formats, but to provide an example of how to use the LockBits method. Этот пример предназначен для использования с Windows Forms.This example is designed to be used with Windows Forms. Чтобы выполнить этот пример, вставьте его в форму и обработки формы Paint событие путем вызова LockUnlockBitsExample , передавая e как PaintEventArgs.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

Комментарии

BitmapData Указывает атрибуты Bitmap, такие как размер, формат пикселей, начальный адрес в памяти данные о пикселях, а длина каждой строки (stride).The BitmapData specifies the attributes of the Bitmap, such as size, pixel format, the starting address of the pixel data in memory, and length of each scan line (stride).

Применяется к