Ubuntu System.windows.forms dont open

Hi guys i Build an app for Linux operative systems. My app load a type of resources, and i used the .NET dll System.windows.forms, i got it from the Unity dlls. In windows i dont haveany problem, the app works perfectly, but when i tried to play on ubuntu dont call the class OpenFileDialog or SaveFileDialog. I also tried to install some apps on ubuntu to fix this, but i didnt work yet. I tried:

sudo apt-get install libmono...runtime...etc

sudo apt-get install libmono...winforms...etc

sudo apt-get install mono-complete

and a few more.

Anyone knows why i cant load my OpenFileDialog or SaveFileDialog?

Thanks guys.