C # upload images to generate thumbnails, control image upload size.

1     #regionUpload a picture to generate a thumbnail image2     /// <summary>3     ///Upload Image4     /// </summary>5     /// <param name= "Sender" ></param>6     /// <param name= "E" ></param>7      Public voidBtnupload_click (Objectsender, EventArgs e)8     {9         //Check that the format of the uploaded file is validTen         if( This. FudPhoto.PostedFile.ContentType.ToLower (). IndexOf ("Image") <0) One         { AResponse.Write ("<script>alert (' Upload image format invalid! '); window.location.href= ' les_applytopactivityadd.aspx ';</script>"); -             return; -         } the         stringFilenmae; -         stringFileNameS; -         stringname = FudPhoto.PostedFile.FileName;//Client file path -FileInfo file =NewFileInfo (name); +         stringFileName =file. Name; -         stringExtname =Getfileext (fileName). ToUpper (); +         //Generate artwork Abyte[] Ofilebyte =New byte[ This. FudPhoto.PostedFile.ContentLength]; atSystem.IO.Stream OStream = This. FudPhoto.PostedFile.InputStream; -System.Drawing.Image Oimage =System.Drawing.Image.FromStream (oStream); -         intTowidth = $;//set thumbnail initial height -         intToheight = $;//set thumbnail initial width -         intx =0; -         inty =0; in         intow =Oimage.width; -         intOh =Oimage.height; to  +         if(ow = =640&& ow = =640) -         { the             //calculates the width and height of the thumbnail proportionally *  $             if(((Double) Oimage.width/(Double) oimage.height) > ((Double) Towidth/(Double) toheight))Panax Notoginseng             { -Oh =Oimage.height; theow = Oimage.height * Towidth/Toheight; +y =0; Ax = (Oimage.width-ow)/2; the             } +             Else -             { $ow =Oimage.width; $Oh = oimage.width * Toheight/Towidth; -x =0; -y = (Oimage.height-oh)/2; the             } -             //Generate thumbnail artworkWuyiBitmap Timage =NewBitmap (Towidth, toheight); theGraphics g =graphics.fromimage (timage); -G.interpolationmode = System.Drawing.Drawing2D.InterpolationMode.High;//setting high-quality interpolation methods WuG.smoothingmode = System.Drawing.Drawing2D.SmoothingMode.HighQuality;//set high quality, low speed rendering smoothness -G.clear (color.transparent);//Empty the canvas and fill it with a transparent background color AboutG.drawimage (Oimage,NewRectangle (0,0, Towidth, Toheight),NewRectangle (0,0, Ow, OH), graphicsunit.pixel); $  -Filenmae = DateTime.Now.ToShortDateString (). Replace ("-","") + DateTime.Now.Hour.ToString () + DateTime.Now.Minute.ToString () + DateTime.Now.Second.ToString () + DateTime.Now.Millisecond.ToString () +"."+ Extname;//Save the physical path to the original -             stringOfullname = Server.MapPath ("/uploadfiles//"+filenmae); -  AFileNameS = Filenmae +"- S"+". JPG";//Save the physical path of the thumbnail image +             stringTfullname = Server.MapPath ("/uploadfiles//"+FileNameS); the             Try -             { $                 //save a picture in JPG format the Oimage.save (Ofullname, System.Drawing.Imaging.ImageFormat.Jpeg); the Timage.save (Tfullname, System.Drawing.Imaging.ImageFormat.Jpeg); the  the                 //Lbmessage.text = "Hint: File" "+ Filenmae +" "Upload successfully and generate" "+ FileNameS +" "thumbnail, File type:" + -                 //FudPhoto.PostedFile.ContentType + ", File size:" + fudPhoto.PostedFile.ContentLength + "B"; inLbmessage.text ="Tip: The file was successfully uploaded and generated ""+ FileNameS +""Thumbnail!" "; the                 stringPIC =Filenmae; theviewstate["pic"] =PIC; About             } the             Catch(Exception ex) the             { the                 Throwex; +             } -             finally the             {Bayi                 //Freeing Resources the oimage.dispose (); the g.dispose (); - timage.dispose (); -             } the         } the         Else the         { theLbmessage.text ="tip: The size of the picture should be 640x640"; -         } the     } the     Private stringGetfileext (stringfileName) the     {94         if(Filename.indexof (".") == -1) the             return ""; the         string[] temp = Filename.split ('.'); the         returnTemp[temp. Length-1]. ToLower ();98     } About     #endregion -}
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C # upload images to generate thumbnails, control image upload size.