“Parameter is not valid” exception from System.Drawing.Image.FromStream() method

问题

I got a hard time with the Image.FromStream method in my website. The code below works perfect on my computer. But when I uploaded it to the test server, it always gives me "Parameter not valid" exception.

if (!afuImageFile.IsUploading && afuImageFile.HasFile)
{
    System.Drawing.Image imgFile = System.Drawing.Image.FromStream(afuImageFile.FileContent);
}

the afuImageFile is an AsynFileUploader control in Ajax Tool Kits. afuImageFile.FileContent is a HttpInputStream. I guess I need to add some permission to some folder. Can anyone help me?

回答1:

Please ensure that your FileContent stream as its position set to 0.

Otherwise, you might want to deactivate image validation by changing the call from:

System.Drawing.Image imgFile = System.Drawing.Image.FromStream(afuImageFile.FileContent);

to:

System.Drawing.Image imgFile = System.Drawing.Image.FromStream(afuImageFile.FileContent, true, false);

See Image.FromStream to check on the other overloads.

来源：https://stackoverflow.com/questions/3586878/parameter-is-not-valid-exception-from-system-drawing-image-fromstream-method