Navigation: ABC Library Reference > ASCIIFileClass > AsciiFileClass Methods >====== GetLine (return line of text)  ====== |    |
GetLine( line number ), PROC
| GetLine | Returns a line of text. |
| line number | An integer constant, variable, EQUATE or expression that contains the offset or position of the line of text to return. |
The GetLine method returns the line of text specified by line number.
Implementation:
The GetLine method gets a line at position line number from the ASCII file, extending the index queue if needed. If the index queue already contains the requested line number then the file is read using the existing offset, otherwise the index is extended. If the requested line number does not exist in the file, the text line is cleared and ERRORCODE() set.
Return Data Type: STRING
Example:
MyViewer.DisplayPage PROCEDURE(LONG LineNo)
LineOffset USHORT,AUTO
CODE
IF LineNo > 0 !line specified?
SELF.ListBoxItems=SELF.ListBox{PROP:Items} !note size of list box
FREE(SELF.DisplayQueue) !free the display queue
SELF.GetLine(LineNo+SELF.ListBoxItems-1) !index to end of page
LOOP LineOffset=0 TO SELF.ListBoxItems-1 !for each listbox line
!read ASCII file record:
SELF.DisplayQueue.Line=SELF.GetLine(LineNo+LineOffset)
IF ERRORCODE() !on end of file
BREAK !stop reading
END
ADD(SELF.DisplayQueue) !add to display queue
END
SELF.TopLine=LineNo !note 1st line displayed
DISPLAY(SELF.ListBox) !redraw the list box
END
See Also: GetLine