I am new to QT programming.

Question

I am new to QT programming. 
Actually I have some source code in C# on the Windows Platform. I would like to convert the code to QT to make it cross-platform. The code is basically a dynamic run-time library.

Can anyone suggest me some tips as in how should I approach this problem. Like how can I convert the entire source code in QT. Because the original code is using some MFC libraries so I need to find some equivalent library in QT or should I rewrite the entire code in QT.

Also What would be the best way to rewrite the entire code?