上传图片并生成略缩图

参数说明FileBox:上传表单中的表单名SavePath:保存路径ThumbnailWidth:略缩图宽ThumbnailHeight:略缩图高FilePath:文件保存路径（输出参数）FileName:文件名称（输出参数）LastError:（输出错误）public static bool UploadImages(System.Web.UI.HtmlControls.HtmlInputFile FileBox,string SavePath,Int32 ThumbnailWidth,Int32 ThumbnailHeight,out String FilePath,out String FileName,out string LastError){DateTime datTime=System.DateTime.Now;String strTemp;string strFileName = FileBox.PostedFile.FileName;bool blnResult;LastError="";System.Drawing.Image xImage;System.Drawing.Bitmap xBitmap;int PhotoHeight,PhotoWidth;string BasePath=System.Web.HttpContext.Current.Server.MapPath("../");Rectangle NewPhoto;System.Drawing.Imaging.ImageFormat xObject;string Extension="";FileName="";FilePath="";try{if(strFileName==""){LastError="请点击浏览选择要上传的文件!";return false;}if(Convert.ToDecimal(FileBox.PostedFile.ContentLength)<= 2000000 &&Convert.ToDecimal(FileBox.PostedFile.ContentLength)>1500){//查看扩展名是否合法Extension=Path.GetExtension(strFileName);Extension=Extension.ToLower();if(Extension==".gif" || Extension==".jpg" || Extension==".jpeg" || Extension==".bmp"){switch(Extension){case ".gif":xObject=System.Drawing.Imaging.ImageFormat.Gif;break;case ".bmp":xObject=System.Drawing.Imaging.ImageFormat.Bmp;break;default:xObject=System.Drawing.Imaging.ImageFormat.Jpeg;break;}}else{LastError="上传的文件不是有效的图片文件，请上传格式为：.gif.jpg.bmp的文件！";return false;}//-----------------------------//生成保存的文件路径及文件名//-----------------------------strTemp = datTime.ToShortDateString().Replace( "-", "");FileName = datTime.ToLongTimeString().Replace(":","")+ Extension;FilePath = SavePath + strTemp + "/";Friendlib.Function.CreateDirectory(BasePath + FilePath);//保存大图xImage=System.Drawing.Bitmap.FromStream(FileBox.PostedFile.InputStream);xImage.Save(BasePath+FilePath+FileName);xImage.Dispose();//-----------------------------//开始生成缩略图//-----------------------------xBitmap=new Bitmap(BasePath+FilePath+FileName);//------------------PhotoHeight=xBitmap.Height;PhotoWidth=xBitmap.Width;// //判断图片的形状 if(Convert.ToDecimal(PhotoHeight)/Convert.ToDecimal(PhotoWidth)>Convert.ToDecimal(ThumbnailHeight)/Convert.ToDecimal(ThumbnailWidth))//高有余 { PhotoHeight=Convert.ToInt16((Convert.ToDecimal(ThumbnailHeight)/Convert.ToDecimal(ThumbnailWidth))*Convert.ToDecimal(PhotoWidth)); NewPhoto=new Rectangle(0,0,PhotoWidth,PhotoHeight); } else if(Convert.ToDecimal(PhotoHeight)/Convert.ToDecimal(PhotoWidth)<Convert.ToDecimal(ThumbnailHeight)/Convert.ToDecimal(ThumbnailWidth)) { PhotoWidth=Convert.ToInt16((Convert.ToDecimal(ThumbnailWidth)/Convert.ToDecimal(ThumbnailHeight))*Convert.ToDecimal(PhotoHeight)); NewPhoto=new Rectangle(Convert.ToInt16((Convert.ToDecimal(xBitmap.Width)-Convert.ToDecimal(PhotoWidth))/2),0,PhotoWidth,PhotoHeight); } else { NewPhoto= newRectangle(0,0,PhotoWidth,PhotoHeight); < BR> } System.Drawing.Image myBitmap; myBitmap=xBitmap.Clone(NewPhoto,System.Drawing.Imaging.PixelFormat.DontCare); System.Drawing.Image.GetThumbnailImageAbort myCallback = new System.Drawing.Image.GetThumbnailImageAbort(ThumbnailCallback); System.Drawing.Image myThumbnail = myBitmap.GetThumbnailImage(ThumbnailWidth,ThumbnailHeight, myCallback, IntPtr.Zero); myThumbnail.Save(BasePath + FilePath +"s"+FileName,xObject); myThumbnail.Dispose(); myBitmap.Dispose(); xBitmap.Dispose(); return true; } else { blnResult=false; LastError="不能上传大于2M及小于1.5K的图片!"; } }< BR> catch (Exception ex) { throw new System.Exception((ex.Message + ("/r/n" + ex.StackTrace))); } return blnResult;}private static bool ThumbnailCallback() { return false; }