Difference between revisions of "GET"

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* File/port number is the number used in the [[OPEN]] AS statement.  
 
* File/port number is the number used in the [[OPEN]] AS statement.  
* The [[INTEGER]] or [[LONG]] byte or record location is the byte in a [[BINARY]] file or the record in a [[RANDOM]] file.
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* The [[INTEGER]] or [[LONG]] byte or record ''position'' is the byte in a [[BINARY]] file or the record in a [[RANDOM]] file.
* Location can be omitted if the GETs are consecutive or when creating a new file.
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* The ''position'' can be omitted if the GETs are consecutive or when creating a new file.
 
* The variable value is any string or number type or a [[TYPE]] or [[FIELD]] variable.
 
* The variable value is any string or number type or a [[TYPE]] or [[FIELD]] variable.
 
* '''QB64''' can GET the entire data contents of an array from a [[PUT]] array file.
 
* '''QB64''' can GET the entire data contents of an array from a [[PUT]] array file.

Revision as of 20:58, 29 April 2011

The GET # file or port device statement reads data by bytes or record positions.


Syntax: GET #filenumber%, [position&], read_variable


  • File/port number is the number used in the OPEN AS statement.
  • The INTEGER or LONG byte or record position is the byte in a BINARY file or the record in a RANDOM file.
  • The position can be omitted if the GETs are consecutive or when creating a new file.
  • The variable value is any string or number type or a TYPE or FIELD variable.
  • QB64 can GET the entire data contents of an array from a PUT array file.
  • GET can ignore the EOF statement and return bad data when transferring data to another file! Always check for EOF after a GET to see if it should be PUT.
  • GET does NOT require a record position or read variable when using a FIELD statement!


Example 1: Checking for End of File before transferring individual GET data.

DO UNTIL EOF(1) GET #1, , value% IF NOT(EOF(1)) THEN PUT #2, , value% LOOP


Example 2: Using a TYPE record variable to read a TYPE record(Contact).

OPEN file$ FOR RANDOM as #1 LEN = LEN(Contact) IF record% <= LOF(1) \ LEN(Contact) THEN GET #1, record%, Contact CLOSE #1

Note: The Contact record contains all of the DOT variable types listed in the TYPE.


Example 3: Restoring array data from a BINARY file using GET # in QB64 only.

DIM myarray(80000) AS INTEGER OPEN "myfile.ext" FOR BINARY AS #1 GET #1, , myarray() CLOSE #1

Note: The file data must have been previously stored in the file using PUT # the same way!


See also:



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