image capture and send with post

[keeneydj]

Ok, like the title suggests, I have a lil paint function
drawing on a canvas in flex 2. What I need is to get that image all
captured and bundled up to send to asp.net VB. The site is here:
we are UNLIMITED .com Click on
start, then Draw, and you will get to play with that canvas. You
can draw all day, different brush sizes, colors, and erase. I need
a capture button there to get the image off the canvas into BYTE
format. Mainly what i need help on is sending that byte array from
flex to asp.net VB, and REALLY need help on catching that byte
array in asp.net VB and getting it to the point i save save it to
the server HDD via the file I/O. I have already been able to save
XML docs to the HDD with asp.net VB to be read by flex via the file
I/O. I really just need some asp.net vb code to do the "POST" catch
(or request), and get the image to PNG? format to be saved. This is
going to be a small paint program in flex, members can use to
create their avatar. I will be implementing say a crop, copy/paste,
drag and drop, resize and what not, to give my users more
flexability as far as what their image looks like. I'd really like
it to be as close to a basic "windows paint" program. But that's
another story. For some reason every time I look up passing
variables from flex (flash) to asp.net vb, it's POSTing form vars,
and really none of it has dealings with images. I know it's
probably really the same, but like I was trying to say, I just get
all kinds of confused with working with byte arrays and asp.net vb
and flex. I was actually supposed to have this site up and running
this past Aug, but with the swap to flex, the pains of membership
between flex and asp.net vb, and my general newbie beginnings of
this whole aspect of computers. Let's just say it's taken a bit
longer than expected.





So to recap from all my babbling:



I need to:

(flex)

Capture the image on that canvas (see link)

load to asp.net VB (pref. using POST)



(asp.net VB)

create an asp.net vb page to receive/request that image

reformat that image ( pref. PNG )

save the formatted image to the server HDD



This should be fairly simple, and I'm almost embarrassed to
ask for help. I've just been trying to work through this muck for
way too long, and I really need to get past this.



code snippets would be great, although just some good
resources to look at would be great too. I do entirely appreciate
any help in this matter.








Daniel Keeney

WebMaster

we are UNLIMITED .com

[hohohuhu]

import com.adobe.images.PNGEncoder;

.....



var canvas:Canvas;

var snapshot:BitmapData = new BitmapData(canvas.width,
canvas.height, true);

snapshot.draw(canvas);



var encBytes:ByteArray = PNGEncoder.encode(snapshot);



// Now you got a byte array.



Hope this help

Note : You will need PNGEncoder from flexlib project.

[keeneydj]

Sweet, that'll get me to a byte array. What I really need,
esp. now, is getting to asp.net. You can also use capture
UIComponent.
http://www.tricedesigns.com/tricedesigns_home/blog/2006/09/flex-2-bitmapdata-tricks-and.html
I like this better. It'll let me set the canvas size first through
variables(canvas creation), then just capture the canvas a lot
easier. Thank you hohohuhu.



Need some good asp.net'ers now. I believe my server allows
coldFusion also, so if we had to go that route to get em to the
server I GUESS that'd be ok ;)



Also now that we just captured as a png, we don't have to do
any formatting on the asp.net side. Just capture and save. When I
was looking up sending form vars from flash to asp.net I was
finding all kinds of POST and LoadVars examples. Now for some
reason I'm not finding any for asp.net. PHP out tha wahzoo though.



Yet again, any help would be freakin awesome.



-Dan

[Former Community Member]

You've probably already worked this one out but I thought I
would post my solution - not elegant but it works



I spent two days trying to find an asp.net solution in VB.net
to no avail so here goes:




Actionscript:



var bitMD:BitmapData = new BitmapData(this.width,this.height)

bitMD.draw(this);



var _PNG:ByteArray = PNGEncoder.encode(bitMD);





var U:URLRequest = new URLRequest

U.method = URLRequestMethod.POST

U.data = _PNG;


U.contentType="application/octet-stream";

U.url = "
http://localhost/CARTO/image.aspx";

var UR:URLLoader = new URLLoader

UR.dataFormat = URLLoaderDataFormat.TEXT

UR.load(U);






ASP.NET



Protected Sub Page_Load(ByVal sender As Object, ByVal e As
System.EventArgs) Handles Me.Load

Dim b() As Byte = Request.BinaryRead(Request.TotalBytes)







Dim ms As MemoryStream = New MemoryStream(b)



Dim img As System.Drawing.Image = Bitmap.FromStream(ms)

Dim bmp As Bitmap = New Bitmap(img)





Dim tempStream As New MemoryStream()

bmp.Save(tempStream, System.Drawing.Imaging.ImageFormat.Png)

Dim fs As New
FileStream(System.Web.HttpContext.Current.Server.MapPath("test.png"),
FileMode.Create)

tempStream.WriteTo(fs)

tempStream.Close()

fs.Close()



End Sub

[keeneydj]

Right on!



That's exactly what I was having trouble with. Reading out of
the memory stream was what I was skipping over. Thank you
Jon