“参数无效。 位于System.Drawing.Bitmap..Ctor（流流）。”

Question

I am getting the "Parameter is not valid.at System.Drawing.Bitmap..ctor(Stream stream)" in my code.

I am using the Following lines in my code,

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

I don't find anything wrong in this code.

Answer 1

In some cases, Bitmap requires a seekable stream. Try:

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

However. I must also note that this looks like ASP.NET; System.Drawing is not supported in ASP.NET: 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.

Answer 2

this solved my problem.

    byte[] fileData = null;
using (var binaryReader = new BinaryReader(Request.Files[0].InputStream))
{
    fileData = binaryReader.ReadBytes(Request.Files[0].ContentLength);
}
ImageConverter imageConverter = new System.Drawing.ImageConverter();
System.Drawing.Image image = imageConverter.ConvertFrom(fileData) as System.Drawing.Image;
image.Save(imageFullPath, System.Drawing.Imaging.ImageFormat.Jpeg);

Answer 3

Also, sometimes you get that invalid parameter when the file exists, but not at that location. I had a similar problem where I was using a relative path, but I forgot to set the image file to copy to the bin directory, so I got the same error. Just FYI

Answer 4

In my case, the folder where the file was located didn't give the application permission to access the file. By trying to read the file directly as a stream, an exception was reported that access was denied. Then I checked the security of the file and folder to discover neither had sufficient permissions to allow the application to read it by a different user. The original "parameter is not valid" error did not give enough information to diagnose the actual problem.