export all the content of r script into pdf

I would want to export all the content of r script into pdf. Could it be possible? I used these commands export, but what I see I just exported graphics

pdf(file = "example.pdf")
  dev.off()

Thank you!

    setwd("C:/Users/Prat/Desktop/c")
    > dir()
    [1] "script.R"> knitr::stitch('script.r')
 output file: script.tex

In my folder doesn't appears a script.pdf else a script.tex and a folder with the pictures in pdf