QB64-PE/internal/help/LINE_INPUT_(file_statement).txt

The '''LINE INPUT #''' file statement reads an entire file line as one string variable value.



{{PageSyntax}}
:: '''LINE INPUT''' '''#'''''filenumber&''''',''' ''textlinereturn$''


{{Parameters}}
* ''filenumber'' is the [[INTEGER]] number of the file previously opened [[AS]].
* Statement [[STRING]] variable returns ''text line'' of the file being read ending at [[ASCII#Control_Characters|CRLF]] characters.


''Description:''
* Reads a file using the filenumber [[OPEN]]ed in the [[INPUT (file mode)]] or GL [[BINARY]] file mode as one file line text string.
* Can be used with [[EOF]] to count the number of lines of data (records) in a file using a loop.
* Use the [[EOF]] function to avoid going past the end of a file and creating an error.
* LINE INPUT # can even retain the original quotation marks in text.
* '''Note: QB64''' will NOT remove CHR$(0) from the end of LINE INPUT # string return values like Qbasic did.
* '''NOTE: [[LINE INPUT (file statement)|LINE INPUT]] will work faster in [[BINARY]] than [[INPUT (file mode)|INPUT]] mode in QB64 to stay compatible with QB.'''


{{PageErrors}}
* '''If QB64 or QB 4.5 give "Input past End of file" errors, check for CHR$(26) in the files being read!'''
* '''Warning! Files must exist to open them in INPUT mode! Use [[_FILEEXISTS]] to avoid program [[ERROR Codes|errors]]!'''


''Example:'' Finding the number of filenames listed in a file to dimension an array to hold them.
{{CodeStart}} '' ''
{{Cl|REDIM}} FileArray$(100) 'create {{Cl|$DYNAMIC|dynamic}} array
{{Cl|SHELL}} {{Cl|_HIDE}} "DIR /B *.* > D0S-DATA.INF"  
{{Cl|IF...THEN|IF}} {{Cl|_FILEEXISTS}}("D0S-DATA.INF") THEN 
  {{Cl|OPEN}} "D0S-DATA.INF" FOR {{Cl|INPUT (file mode)|INPUT}} AS #1 
  DO UNTIL {{Cl|EOF}}(1)
    {{Cl|LINE INPUT}} #1, file$        'read entire text file line
    filecount% = filecount% + 1
  LOOP
  {{Cl|CLOSE}} #1
{{Cl|END IF}}
{{Cl|REDIM}} FileArray$(filecount%)
{{Cl|PRINT}} filecount% '' ''
{{CodeEnd}}


''See also:'' 
* [[OPEN]], [[CLOSE]]
* [[INPUT (file mode)]], [[INPUT (file statement)|INPUT #]], [[INPUT$]] {{text|(file input)}}
* [[INPUT]], [[LINE INPUT]], [[INPUT$]] {{text|(keyboard input)}}
* [[_FILEEXISTS]], [[_DIREXISTS]]
* [[FILELIST$]] (Function replacement for [[FILES]])


{{PageNavigation}}