Parsing from Textbox to Listbox

[Miha]

Hello im new here and to programing.
At the moment i am trying to code a program that would load a webpage in Textbox, then parse number between var lv_screenshots = [{id: and ,user then add it to listbox as NUMBER URL.Text X
Number is number that was parsed, Url.Text is where page was and X is a number after webpage.(www.webpage.com/?something=21343).
I had managed to get page itro textbox then output page address with x itro listbox but i do not know how to parse limited data from textbox itro listbox.
Also i would like to ask how could i make this loop until x reaches value y or Stop Button is pressed.

Edit:Im using VB6