Box SUB

 Action
 Draws a box around a defined area, using the foreground and background
 colors specified.


 Syntax
 Box row1%, col1%, row2%, col 2%,  fore%, back%, border$,  fillflag%

 Remarks
 The Box procedure uses the following arguments.

 row1%, col1%
 ------------
 An integer pair that specifies absolute screen row and column coordinates.

 row2%, col 2%
 -------------
 An integer pair that specifies the lower-right corner coordinates of an
 area.
 fore%    An integer that defines the foreground color (0 - 7)

 back%
 -----
 An integer that defines the background color (0 - 15).

 border$
 -------
 Nine-character string that defines the characters that are used to create
 the box. Each character position is significant because it defines a
 particular part of the box. Characters are defined as follows.

 Position    Character described

     1        Upper-left-corner character
     2        Top-line character
     3        Upper-right-corner character
     4        Left-side line character
     5        Fill character for middle area
     6        Right-side line character
     7        Lower-left-corner character
     8        Bottom-line character
     9        Lower-right-corner character

 fillflag%
 ---------
 TRUE (-1) if the interior of the box is to be cleared;
 FALSE (0) if it is not.

 The Box procedure is used in WINDOW.BAS to draw boxes on the screen.

 The individual character entries in the argument border$ define which
 characters are used to draw the box. You can use any characters in either
 the standard ASCII or extended character set. Normally, box characters in
 the range CHR$(179) through CHR$(218) are used. (The figure on the following
 page shows the box characters and their corresponding ASCII codes.)


 Figure 3.1  Box border characters and their corresponding ASCII codes

 Box characters can be entered by pressing the Alt key and the appropriate
 numbers on the keypad. The function of each of the nine character positions
 in the argument border$ is shown in the table above.

 If fewer than nine characters are included in border$, a default single-line
 box is drawn; if more than nine characters are included, only the first nine
 are used.

 See Also.  WindowBox, WindowDo, WindowOpen