C # generate thumbnail code

Thumbnail if (fileupload. Postedfile!=null)
{
AddTo for the property to be added, Aboutfile for the file description
String nam = FileUpload. Postedfile.filename;
Gets the last "." in the filename (enclosing path). The index
int i= Nam. LastIndexOf (".");
Get file name extension
String Newext =nam. Substring (i);
Here I automatically name the file according to the date and file size to ensure that the filename is not duplicated
DateTime now = DateTime.Now;
String Newname=now. Dayofyear.tostring () +fileupload. PostedFile.ContentLength.ToString ();
Save the file to the directory you want, this is the upload directory under the IIS root directory. You can change.
Note: I use Server.MapPath () to get the relative directory of the current file. In asp.net "\" must be replaced by "\", the "upload\\" to "\\upload\\" has become the absolute directory of the current file
FileUpload. Postedfile.saveas (Server.MapPath ("upload\\" +newname+newext));
Get the related attributes of this file: file name, file type, file size
FName. Text=myfile.postedfile.filename;
Fenc. Text=myfile.postedfile.contenttype;
Fsize. Text=myfile.postedfile.contentlength.tostring ();
Here is the build thumbnail
System.Drawing.Image Image,anewimage;
int width,height,newwidth,newheight;
Image=system.drawing.image.fromfile (Server.MapPath) ("upload/" +newname. ToString () +newext. ToString ()));
System.Drawing.Image.GetThumbnailImageAbort callb =new System.Drawing.Image.GetThumbnailImageAbort ( Thumbnailcallback);
Width=image. Width;
Height=image. Height;
if (firstpageshow. selectedvalue.tostring () = = "1" &&fenlei. selectedvalue.tostring () = = "5")
{
newwidth=203;newheight=86;
Newheight=height*newwidth/width;
}
else if (Isweekman. selectedvalue.tostring () = = "1")
{
newwidth=171;newheight=111;
Newheight=height*newwidth/width;
}
else if (firstpageshow. selectedvalue.tostring () = = "1" &&fenlei. selectedvalue.tostring () = = "3")
{
newwidth=171;newheight=111;
Newheight=height*newwidth/width;
}
Else
{
newwidth=62;newheight=80;
Newheight=height*newwidth/width;
}
Anewimage=image. Getthumbnailimage (Newwidth,newheight,callb,new system.intptr ());
Anewimage.save (Server.MapPath ("upload\\" + "Small_" +newname+newext));
Image. Dispose ();
Build and save the thumbnail, save name is added a Small_ before the original name.
Pic= "upload/" +newname. ToString () +newext. ToString ();
Smallpic= "Upload/small_" +newname. ToString () +newext. ToString ();
}