基本上我想在ASP.NET处理程序,以呈现一个简单的图片:无法呈现图像HttpContext.Response.OutputStream
public void ProcessRequest (HttpContext context)
{
Bitmap image = new Bitmap(16, 16);
Graphics graph = Graphics.FromImage(image);
graph.FillEllipse(Brushes.Green, 0, 0, 16, 16);
context.Response.ContentType = "image/png";
image.Save(context.Response.OutputStream, ImageFormat.Png);
}
,但我得到以下异常:
System.Runtime.InteropServices.ExternalException: A generic error
occurred in GDI+.
at System.Drawing.Image.Save(Stream stream, ImageCodecInfo encoder,
EncoderParameters encoderParams)
的解决方法是使用此代替图像写入OutputStream:
MemoryStream temp = new MemoryStream();
image.Save(temp, ImageFormat.Png);
byte[] buffer = temp.GetBuffer();
context.Response.OutputStream.Write(buffer, 0, buffer.Length);
所以我只是好奇为什么第一个变体是有问题的?
编辑:HRESULT是80004005这只是“通用”。
您的解决方案使用的GetBuffer(),必须你在`Response.OutputStream.Write`之后放置`Image`和`MemoryStream`对象? – Pingpong 2017-08-18 00:23:27