Resolving unhandled exception problems with CF 3.5 Bitmap (Stream) in asp.net

VS2008 development environment, when programming wm sockets under. NET CF 3.5

Bitmap BMP = Unhandled exception occurred at New Bitmap (Stream)

By groping, I find that the problem persists regardless of how the object is set to null and Dispose.

The reason, the individual guess is bitmap instantiation of itself will open MemoryStream flow, so then use MemoryStream is very easy to leak memory

Therefore, it is recommended that when combined with bitmap, replace the MemoryStream with FileStream or other workarounds and reclaim the memory in a timely manner.

The following are examples of using references:

The main function is: Photo upload.

The code is as follows

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View Code public class Photohelper { BaseForm _form; Photo Upload Form TextBox _txtfilename; Show Photo Path PictureBox _picphoto; Show photo thumbnails Public Photohelper (BaseForm form,textbox txtfilename,picturebox Picphoto) { _form = form; _txtfilename = Txtfilename; _picphoto = Picphoto; _picphoto.image = new Bitmap (300, 350); }                #region Camera logic         public void Takephoto ()         {             //Photo-----------------------------                      cameracapturedialog CCD = new CameraCaptureDialog ();             CCD. Mode = Cameracapturemode.still;             CCD. Owner = _form;             CCD. Title = "Photograph";             CCD. Resolution = new Size (1600, 1200);             CCD. stillquality = Cameracapturestillquality.normal;             if (CCD. ShowDialog () = = DialogResult.OK)             {                //will be photographed in thumbnail display                 Imagechangedargs args = new Imagechangedargs (CCD. FileName);                 using (Graphics g = Graphics.fromimage (_picphoto.image))                  {                      g.drawimage (args. Image,                          New Rectangle (0, 0, _picphoto.image.width, _picphoto.image.height),                          New Rectangle (0, 0, args. Image.width, args. Image.height),                          GraphicsUnit.Pixel); } Args. Dispose (); args = null; _txtfilename.text = CCD. FileName; } Ccd. Dispose (); CCD = NULL; } #endregion #region Photo Upload logic public void Photosave () { if (string. IsNullOrEmpty (_txtfilename.text)) { Global.showmsg ("No photos to upload"); Return } string prompt = "Confirm upload photo?" "; if (global.showyesnomsg (prompt) = = dialogresult.no) Return Convert photo to byte[] Byte[] B = filetobytes (_txtfilename.text); #region Todo will byte[] upload the server via WebService, please add your own code here Commandandtaskidobj commandobj = _form.commandandtaskidobj; Wsrmsg msg = Global.getservice (). Upfile (Commandobj.username, Commandobj.commandid, Commandobj.taskid, B, _txtfilename.text); if (Msg. Flag = 0) //{ b = null; throw new Exception (Msg. EMSG); //} #endregion Global.showmsg ("Photo upload success"); _txtfilename.text = string. Empty; b = null; } #endregion Static byte[] Filetobytes (string sfilepath) { FileStream inFile = null; Try { Byte[] BinaryData; InFile = new FileStream (Sfilepath, FileMode.Open, FileAccess.Read); BinaryData = new Byte[infile.length]; Long bytesread = Infile.read (binarydata, 0, (int) infile.length); return binarydata; } catch (Exception ex) { Throw ex; } Finally { if (inFile!= null) { Infile.close (); Infile.dispose (); } InFile = null; } } internal void Photodispose () { throw new NotImplementedException (); } } public class Imagechangedargs:eventargs, IDisposable { Private Bitmap image; <summary> Used to create the thumbnail </summary> private stream stream; Public Imagechangedargs (String imagefilepath) { Try { This.stream = new FileStream (Imagefilepath, FileMode.Open, FileAccess.Read); This.image = new Bitmap (this.stream); } catch (Exception ex) { This.image = null; if (This.stream!= null) { This.stream.Close (); This.stream = null; } } }         public Bitmap Image         {             Get              {                  return this.image;            }        } Public Stream Stream { Get { return this.stream; } } #region IDisposable Members public void Dispose () { if (this.image!= null) This.image.Dispose (); This.image = null; if (This.stream!= null) { This.stream.Close (); This.stream.Dispose (); } This.stream = null; } #endregion }

As can be seen from the last example, the MemoryStream class is basically replaced by FileStream.

When a large picture is loaded, the exception exception is not reported as long as the memory allows