c# - GDI+ 在 c# 循环中将位图保存到文件时发生一般错误

Question

我在一个循环中将位图保存到我硬盘上的一个文件中(一个目录中的所有 jpeg 文件都被保存到一个数据库中)。保存在第一次通过循环时工作正常，但在第二次通过时给出主题错误。我想也许文件被锁定了，所以我尝试为每次传递生成一个唯一的文件名，并且在文件保存后我也在位图上使用 Dispose() 。知道是什么导致了这个错误吗？

这是我的代码:

private string fileReducedDimName = @"c:\temp\Photos\test\filePhotoRedDim";
...
foreach (string file in files)
{
    int i = 0;

    //if the file dimensions are big, scale the file down
    Stream photoStream = File.OpenRead(file);
    byte[] photoByte = new byte[photoStream.Length];
    photoStream.Read(photoByte, 0, System.Convert.ToInt32(photoByte.Length));
    Image image = Image.FromStream(new MemoryStream(photoByte));
    Bitmap bm = ScaleImage(image);
    bm.Save(fileReducedDimName + i.ToString() + ".jpg", ImageFormat.Jpeg);//error occurs here
    Array.Clear(photoByte,0, photoByte.Length);
    bm.Dispose();

    i ++;
}
...

谢谢

这是比例图像代码:(这似乎工作正常)

protected Bitmap ScaleImage(System.Drawing.Image Image)
    {
        //reduce dimensions of image if appropriate
        int destWidth;
        int destHeight;
        int sourceRes;//resolution of image
        int maxDimPix;//largest dimension of image pixels
        int maxDimInch;//largest dimension of image inches
        Double redFactor;//factor to reduce dimensions by
        if (Image.Width > Image.Height)
        {
            maxDimPix = Image.Width;
        }
        else
        {
            maxDimPix = Image.Height;
        }
        sourceRes = Convert.ToInt32(Image.HorizontalResolution);
        maxDimInch = Convert.ToInt32(maxDimPix / sourceRes);

        //Assign size red factor based on max dimension of image (inches)
        if (maxDimInch >= 17)
        {
            redFactor = 0.45;
        }
        else if (maxDimInch < 17 && maxDimInch >= 11)
        {
            redFactor = 0.65;
        }
        else if (maxDimInch < 11 && maxDimInch >= 8)
        {
            redFactor = 0.85;
        }
        else//smaller than 8" dont reduce dimensions
        {
            redFactor = 1;
        }
        destWidth = Convert.ToInt32(Image.Width * redFactor);
        destHeight = Convert.ToInt32(Image.Height * redFactor);
        Bitmap bm = new Bitmap(destWidth, destHeight,
            PixelFormat.Format24bppRgb);
        bm.SetResolution(Image.HorizontalResolution, Image.VerticalResolution);
        Graphics grPhoto = Graphics.FromImage(bm);
        grPhoto.InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.HighQualityBicubic;

        grPhoto.DrawImage(Image,
            new Rectangle(0, 0, destWidth, destHeight),
            new Rectangle(0, 0, Image.Width, Image.Height),
            GraphicsUnit.Pixel);

        grPhoto.Dispose();
        return bm;

    }

Answer 1

如果我没看错代码，你的 i 变量在每次循环中都是零。