Incrementing character field and leading 0's

[Jeff Moses]

Thanks to Bill a Jerry's answer in a previous post I have been successful in auto incrementing a via x basic. I have run into one other problem. One of the fields that i need to auto increment was started off in about 20 applications with "000001". If the value starts with any zeros they are droped. Below are two working scripts but leading zeros are always droped.

''Script one
dim temp_c as c
t = table.open("inv_hdr")
t.fetch_last()
temp_c=str(val(substr(t.inv_no,1,7))+1,7,0)
t.enter_begin()
t.inv_no=temp_c
t.enter_end(.t.)
t.close()
end

''Scritp two
dim temp_c as c
t = table.open("inv_hdr")
t.fetch_last()
temp_c = str(Val(t.inv_no)+1,7,0)
t.enter_begin()
t.inv_no=temp_c
t.enter_end(.t.)
t.close()
end
These scripts will also leave 2 or blank spaces to the left and right so if I start with "000001". The script ends up creating a value of " 2 ".
Any ideas how modify either script to salvage the leading zeros
Thanks, Jeff

[csda1]

RE: Incrementing character field and leading 0's

Jeff,

Use something like this

temp_c = padl(ltrim(str(Val(t.inv_no)+1,7,0)),7,"0")

Regards,

Ira J. Perlow
Computer Systems Design & Associates
[email protected]

[whanigsberg]

RE: Incrementing character field and leading 0's

Jeff,

Use the padl (pad left) function to pad out the resulting string to the required length. The function allows you to the width of the result and the character with which to pad.

Hence, from the interactive window:
temp_c = "2"
temp_c = padl(temp_c,7,"0")
?temp_c
= "0000002"

I had to do a lot of this sort of manipulation in order to take a course section number and augument it in order to generate a default for the next section which I could check for uniqueness (since you can't have two course sections in the same term with the same number). What made the problem difficult was that the section numbers sometimes contain non-numeric characters, (eg. to distinguish between a class and a lab). I had to remove these, increment the number, and then reinsert the non-numeric character(s).

It got a bit gothic.

This leads me to another suggestion which is rather obvious. You might want to consider creating a function to do the increment. It really cleans up your code and makes it easier to understand.

For example, when I want to generate a course section I need only write

next_section(previous_section)

since the two pages of heavy lifting to create the new number are in the custom function called "next section".

Bill