Resize image in asp.net Size readonly error

Question

I want to resize the image coming through file uploader. For that I was referred to the following:

How to set Bitmap.Width and Bitmap.height

(Javed Akram's Answer)

Made following code:

Dim imgSmall As Bitmap = New Bitmap(FUpload.PostedFile.InputStream, False)
imgSmall.Size = New Size(250, 300)

But giving me error:

Size is read-only property.

How can I resize the image in this case?

sh1rts · Accepted Answer · 2013-11-27T23:06:45.557

It is read-only; you'll have to create a new bitmap from it. Try this: -

internal static Image ScaleByPercent(Image image, Size size, float percent)
{
    int sourceWidth  = image.Width,
        sourceHeight = image.Height;

    int destWidth  = (int)(sourceWidth * percent),
        destHeight = (int)(sourceHeight * percent);

    if (destWidth <= 0)
    {
        destWidth = 1;
    }

    if (destHeight <= 0)
    {
        destHeight = 1;
    }

    var resizedImage = new Bitmap(destWidth, destHeight, PixelFormat.Format24bppRgb);
    resizedImage.SetResolution(image.HorizontalResolution, image.VerticalResolution);

    // get handle to new bitmap
    using (var graphics = Graphics.FromImage(resizedImage))
    {
        InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.HighQualityBicubic;

        // create a rect covering the destination area
        var destRect = new Rectangle(0, 0, destWidth, destHeight);
        var brush    = new SolidBrush(drawing.Color.White);
        graphics.FillRectangle(brush, destRect);

        // draw the source image to the destination rect
        graphics.DrawImage(image,
                            destRect,
                            new Rectangle(0, 0, sourceWidth, sourceHeight),
                            GraphicsUnit.Pixel);
    }

    return resizedImage;
}

This is from a site I have in production; if you want I can send you the code that works out how to keep the correct aspect ratio when resizing (i.e. what gets passed in the 'size' parameter)

Hope that helps

Resize image in asp.net Size readonly error

1 Answers1