String to int and int to sting conversion

I have the same problem:

What i want to do is to turn a int number (for example 14 ) to the string "14", in order to use it to get an image. An example:

---code---

global tankimagenumber:int=14

global tankimagestring:string

tankimagestring.Fromint(tankimagenumber)

global tankimage:TImage=loadimage("images/tank"+tankimagestring+".png",MASKEDIMAGE) 'knowing that the image file's url is "images/tank14.png"

---end of code---

This doesn't work... what should i do?