Extract certain variable numbers from attached file title

Fred good job !!!

I just add 3 groups to remove the 0 before the significant digit. 
I also replaced the "[^0-9]+" by "-" and "+" which are signs directly present in the filename structure : (0*)(\d+)-(0*)(\d+)x(0*)(\d+)

Now the 0 at the beginning of the number is removed. For example, the file number goes from 001 to 1. It can be converted directly by Ninox to create a JSON.

the group $0 contain the begin of name.
$1 all zero before significant digit of Numero intero. $2 contain Numero intero.
$3 all zero before significant digit of Larghezza. $4 contain Larghezza. 
$5 all zero before significant digit of Altezza. $6 contain Altezza. 

var values := parseJSON(
       extractx("NAME-Nr001-200x400cm-Backlight-2021",
                "(0*)(\d+)-(0*)(\d+)x(0*)(\d+)",
                "",
                "{""Numero intero"":$2, ""Larghezza"" :$4, ""Altezza"" : $6}")
            );

this.'Numero intero' := values.'Numero intero';
this.Larghezza := values.Larghezza;
this.Altezza := values.Altezza;

This new formula returns directly a JSON variable which contains the three values extracted from the file : " Numero intero ", " Larghezza ", " Altezza ". It is easy to assign them to the corresponding fields in the record.

If you want to test another regular expression, I invite you to try this web site : https://regex101.com/r/cO8lqs/3

I stayed away with hard coding the "-" and the "x" as I wanted to make something that was more flexible. I guess dropping the leading 0's are ok. I went the with what was in front of me. I like the use of the JSON. It is easier to read and keep track of.

Fred of course, you're right is better to stay away "-" and "x" .

Also, if you replace [^0-9]+ by ^[1-9]+, it's replace my (0*) and it stay only 3 groups (not 6) : 

[^1-9]+(\d+)[^1-9]+(\d+)[^1-9]+(\d+)

var values := parseJSON(
       extractx("NAME-Nr001-200x400cm-Backlight-2021",
                "[^1-9]+(\d+)[^1-9]+(\d+)[^1-9]+(\d+)",
                "",
                "{""Numero intero"":$1, ""Larghezza"" :$2, ""Altezza"" : $3}")
            );

warning : it work only if each number is not over 0.

Fred It to convert string number to JSON number...

extractx("NOM-Nr001-200x400cm-Backlight-2021", "(\d+)[^0-9]+(\d+)[^0-9]+(\d+)", "", "{""Numero intero"":$1}"), return {"Numero intero":001}.

parseJSON("{""Numero intero"":001}") return nothing because 001 is not a number.

While extractx("NOM-Nr001-200x400cm-Backlight-2021", "[^1-9]?+(\d+)[^1-9]+(\d+)[^1-9]+(\d+)", "", "{""Numero intero"":$1}"), return {"Numero intero":1}.

And parseJSON("{""Numero intero"":1}") return {"Numero intero":1}.