ONE week back

[sal21]

I have this a var filled with 20100607-20100611 is a week

How to calculate (and return in the same format) a week back based thi var?

in this case the new var = 20100531-20100604

[HansV]

I'd use a date variable instead, and calculate the string from it:

Dim dtmDate As Date
Dim strWeek As String

dtmDate = DateSerial(2010,6,7)
strWeek = Format(dtmDate, "yyyymmdd") & "-" & Format(dtmDate + 4, "yyyymmdd")

To go back a week, simply subtract 7 from dtmDate.

[sal21]

I'd use a date variable instead, and calculate the string from it:

Dim dtmDate As Date
Dim strWeek As String

dtmDate = DateSerial(2010,6,7)

strWeek = Format(dtmDate, "yyyymmdd") & "-" & Format(dtmDate + 4, "yyyymmdd")

To go back a week, simply subtract 7 from dtmDate.

dtmDate = DateSerial(2010,6,7)
wich part of my string i can insert???

[HansV]

Where does the string come from? If possible, you should avoid using it.

[Goshute]

I have this a var filled with 20100607-20100611 is a week

How to calculate (and return in the same format) a week back based thi var?

in this case the new var = 20100531-20100604

I agree strongly with Hans that it's much easier to Dimension dates as Date Type and work with them that way. However, where your strings are
Dim myWeekString as String, strNewVar as String
see if this works:

strNewVar = format(dateserial(left(myWeekString, 4),mid(myWeekString, 5,2),mid(myWeekString, 7,2)-7),"yyyymmdd") & "-" & format(dateserial(mid(myWeekString, 10,4),mid(myWeekString, 14,2),mid(myWeekString, 16,2)-7),"yyyymmdd")

[sal21]

I have this a var filled with 20100607-20100611 is a week

How to calculate (and return in the same format) a week back based thi var?

in this case the new var = 20100531-20100604

I agree strongly with Hans that it's much easier to Dimension dates as Date Type and work with them that way. However, where your strings are
Dim myWeekString as String, strNewVar as String
see if this works:

strNewVar = format(dateserial(left(myWeekString, 4),mid(myWeekString, 5,2),mid(myWeekString, 7,2)-7),"yyyymmdd") & "-" & format(dateserial(mid(myWeekString, 10,4),mid(myWeekString, 14,2),mid(myWeekString, 16,2)-7),"yyyymmdd")

Godd solution......... tks.