How can I lock the UI scrollbar's position when it reaches a certain value? a

[CarbonLayers]

The scrollbar in javascript has a .value attribute. When the value = 100 out of 200, I would like the position of the scrollbar to then be prevented from visually and numerically moving any further. Is there an attribute that can control these in javascript? 

[CarbonLayers]

Sorry not the scrollbar itself, but the little scroller you click and drag inside of it.

[JJMack]

What make you think a Photoshop Script can do anything to Photoshop UI scroll bars?  Even using Photoshop UI interactivity you can not lock a scroll bar slider at some position.  There is no  position numerical value indicator either. There is no reference to SCROLL if you search Adobe Javascript reference and the scriptlistener plug-in does not record any actions manager code when you scroll an image. Also the are no shortcuts for scrolling or menu menu  item for scrolling images. 

[jazz-y]

scrollbar.onChanging = function () {this.value = this.value >= 100 ? 100 : this.value}

[JJMack]

I thought the OP was referring to an image's  scrollbar not a dialog  scriptui scrollbar. I missed the UI int the title....