C# GDI+ Image Resize Function

Question

So my logic is flawed and I need a better and correct way to resize an image in my c# app

I need a function similar to this setup

public void ResizeI         


        

Answer 1

This is code I've used to resize images that users upload to either create a thumbnail or simply to enforce a size restriction. It doesn't address picture quality, but it's a start.

// uses System.Drawing namespace
public class ImageResizer
{
    public bool ResizeImage(string fullFileName, int maxHeight, int maxWidth)
    {
        return this.ResizeImage(fullFileName, maxHeight, maxWidth, fullFileName);
    }

    public bool ResizeImage(string fullFileName, int maxHeight, int maxWidth, string newFileName)
    {
        using (Image originalImage = Image.FromFile(fullFileName))
        {
            int height = originalImage.Height;
            int width = originalImage.Width;
            int newHeight = maxHeight;
            int newWidth = maxWidth;

            if (height > maxHeight || width > maxWidth)
            {
                if (height > maxHeight)
                {
                    newHeight = maxHeight;
                    float temp = ((float)width / (float)height) * (float)maxHeight;
                    newWidth = Convert.ToInt32(temp);

                    height = newHeight;
                    width = newWidth;
                }

                if (width > maxWidth)
                {
                    newWidth = maxWidth;
                    float temp = ((float)height / (float)width) * (float)maxWidth;
                    newHeight = Convert.ToInt32(temp);
                }

                Image.GetThumbnailImageAbort abort = new Image.GetThumbnailImageAbort(ThumbnailCallback);
                using (Image resizedImage = originalImage.GetThumbnailImage(newWidth, newHeight, abort, System.IntPtr.Zero))
                {
                    resizedImage.Save(newFileName);
                }

                return true;
            }
            else if (fullFileName != newFileName)
            {
                // no resizing necessary, but need to create new file 
                originalImage.Save(newFileName);
            }
        }

        return false;
    }

    private bool ThumbnailCallback()
    {
        return false;
    }
}