Use of properties class

I have the following Ascii file named wscnt:

#Sat Oct 08 08:34:32 CEST 2005

#contatore progressivo corrente
contatore=0000100

#contatore iniziale
iniziale=0000100

#limite contatore
limite=0000110


I like to read the value of "contatore" wich initially is 0000100

Increment it of 1 unit

and write it back in the file wscnt.

I am able to read it but I am unable to rewrite the file updated.

Can anyone write for me the few correct statements to do this?

Thank you and Happy new year. Franco

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