REM >strcomp
shav$ = "Shaw, George Bernard"
shakes$ = "Shakespeare, William"
:
REM test equality
IF shav$ = shakes$ THEN PRINT "The two strings are equal" ELSE PRINT "The two strings are not equal"
:
REM test inequality
IF shav$ <> shakes$ THEN PRINT "The two strings are unequal" ELSE PRINT "The two strings are not unequal"
:
REM test lexical ordering
IF shav$ > shakes$ THEN PRINT shav$; " is lexically higher than "; shakes$ ELSE PRINT shav$; " is not lexically higher than "; shakes$
IF shav$ < shakes$ THEN PRINT shav$; " is lexically lower than "; shakes$ ELSE PRINT shav$; " is not lexically lower than "; shakes$
REM the >= and <= operators can also be used, & behave as expected
:
REM string comparison is case-sensitive by default, and BBC BASIC
REM  does not provide built-in functions to convert to all upper
REM or all lower case; but it is easy enough to define one
:
IF FN_upper(shav$) = FN_upper(shakes$) THEN PRINT "The two strings are equal (disregarding case)" ELSE PRINT "The two strings are not equal (even disregarding case)"
END
:
DEF FN_upper(s$)
LOCAL i%, ns$
ns$ = ""
FOR i% = 1 TO LEN s$
  IF ASC(MID$(s$, i%, 1)) >= ASC "a" AND ASC(MID$(s$, i%, 1)) <= ASC "z" THEN ns$ += CHR$(ASC(MID$(s$, i%, 1)) - &20) ELSE ns$ += MID$(s$, i%, 1)
NEXT
= ns$