Select All values from Mutli select List Box


I have a Multi select List box which pulls values from a column. which in turn populates a different values based on another document property.

I want a script/button which will allow users to select all the values present in the Multi-select List Box document property.

I am zero when it comes to coding. So I would appreciate it if you could give me a sample code which I can use. Also I would be obliged if you can explain to me what each line does so I can learn in the process.



(1) Answer