display a picture generated by a .net dll

[NicolasChristnacher]

Hi community,

I'm facing an issue when I want to display a picture (barcode) generated by a .Net Library made by a colleague.

I create with labview an object call "barcode" from this Library and invoke the node barcode which is returning a System.Drawing.Image and I can't display this Image on labview.

Someone has already done something similar?

You will find attached the dell and VI I wrote.

[Artem.SPb]

Save to LV14 or earlier, please.

[NicolasChristnacher]

Hi,

Here is the LV 2014 version

[wiebe@CARYA]

From the Bitmap, you'll need to get the Width and Height properties, and then use GetPixel(X,Y) to build a 2D array. Then convert that to a pixmap using Unflatten Pixmap, and then (if required) to a picture control with Draw Flattened Pixmap.

Note that the dll doesn't load correctly (or run), there are probably missing dependencies.

[alexderjuengere · Accepted solution]

---

when you feed the "encode" reference into a generic property node, spawn some indicators e.g. "height" and run the .vi,

this is happening:

so, either your input parameters result in an empty image, or as wiebe suggested:

wiebe@CARYA wrote:

Note that the dll doesn't load correctly (or run), there are probably missing dependencies.

EDIT: already the first "bar code" methode node indicates

1386 error

after running the .vi

[NicolasChristnacher]

Thanks for your answer,

I wrote to the dll developper and wait for his answer

[NicolasChristnacher]

I modify width and height inputs value and it's working but I have something strange: the picture box is erased once run is finish, if I want to see the barcode in the picture box I have to run continuously.

[wiebe@CARYA]

When the VI stops, it releases some resources. Continuous run is probably not needed, but you'll have to make sure the VI doesn't stop. For instance, drop a Wait with 10000 ms, or an event structure on the diagram to prevent the VI from going to idle.

[Yamaeda]

LabVIEW closes references after a run, so that sounds reasonable. If you just add a wait or have it as part of a bigger program it shouldn't be a problem.

/Y

[wiebe@CARYA]

Usually, I'd avoid .NET objects but in stead get LabVIEW data asap.

It is not easy, but possible, to get a LV Pixmap from the image. See attached VI saved to LV2013.

Note that I get your image from file. You should be able to figure that out. Also note it's not been tested very toughly. There might be memory leaks or even crashes, since the marshal object relates to "unmanaged" data (pointer stuff). It seems fine though.