FIELD

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Supported in Just BASIC Supported in Liberty BASIC Not supported in Liberty BASIC 5 Not supported in Run BASIC

Description

A FIELD is a variable that is given a name and size and identifies a piece of data that is part of a record in a random access file (RAF). All records in a file are structurally identical; They all have the same FIELDs.
See also, GET, PUT, and Random access files.

Syntax

  1. field #handle, length1 as varName, length2 as varName, . . .

Hints

FIELDs must be defined before a RAF can be accessed. They are defined with a name and a size - the number of characters to allow for the data that FIELD will hold. The sum of the sizes of all of the fields make up the length of a record. The length is assigned to the keyword "len" at the end of the Open "fileName" statement. The value of "len" must be equal to the sum of the field sizes.
You cannot create FIELDS with sum of the field sizes more then 65536 bytes.

Example

  ' open a random access file
  open "custdata.001" for random as #cust len = 70

  ' define the field variables
  field #cust, 20 as name$,_
               20 as street$,_
               15 as city$,_
                2 as state$,_
               10 as zip$,_
                3 as age

[inputLoop]
  input "Name >"; name$
  input "Street >"; street$
  input "City >"; city$
  input "State >"; state$
  input "Zip Code >"; zip$
  input "Age >"; age

  ' ask if the data is entered correctly
  confirm "Is this entry correct?"; yesNo$
  if  yesNo$ = "no" then [inputLoop]

  ' add 1 to the record # and put the record
  recNumber = recNumber + 1
  put #cust, recNumber

  ' ask whether to enter more records
  confirm "Enter more records?"; yesNo$
  if yesNo$ = "yes" then [inputLoop]

  ' end of program, close file
  close #cust
  end

Useful Procedures

' Place a useful function or sub using this keyword here