c# - "Parameter is not valid. At System.Drawing.Bitmap..Ctor (Stream stream)."

Question

我收到“Parameter is not valid.at System.Drawing.Bitmap..ctor(Stream stream)” 在我的代码中。

我在我的代码中使用了以下行，

System.Drawing.Bitmap image = new System.Drawing.Bitmap(fileUpload1.PostedFile.InputStream);

我没有发现这段代码有任何问题。

Answer 1

在某些情况下，Bitmap 需要一个seekable 流。尝试:

Bitmap image;
using(var ms = new MemoryStream()) {
    fileUpload1.PostedFile.InputStream.CopyTo(ms);
    ms.Position = 0;
    image = new System.Drawing.Bitmap(ms);
}

但是。我还必须注意，这看起来像 ASP.NET； System.Drawing在 ASP.NET 中不受支持:see here

Classes within the System.Drawing namespace are not supported for use within a Windows or ASP.NET service. Attempting to use these classes from within one of these application types may produce unexpected problems, such as diminished service performance and run-time exceptions. For a supported alternative, see Windows Imaging Components.