Campbell Scientific CR1000KD CR1000 Measurement and Control System - Page 238

Section 7. Installation Table 39. String Concatenation Examples Expression Comments Str(1) = 5.4 + 3 + " Volts" Add floats, concatenate strings Str(2) = 5.4 & 3 & " Volts" Concatenate floats and strings Lng(1) = "123" Convert string to long Lng(2) = 1+2+"3" Add floats to string / convert to long Lng(3) = "1"+2+3 Concatenate string and floats Lng(4) = 1&2&"3" Concatenate floats and string Result "8.4 Volts" "5.43 Volts" 123 33 123 123 7.8.13.3 String NULL Character All strings are automatically NULL terminated. NULL, Chr(0) or "", counts as one of the characters in the string. Assignment of just one character is that character followed by a NULL, unless the character is a NULL. Table 40. String NULL Character Examples Expression Comments Result LongVar(5) = "#"-"" Subtract NULL, ASCII code results 35 LongVar(6) = StrComp("#","") Also subtracts NULL 35 Example: Objective: Insert a NULL character into a string, and then reconstitute the string. Given: StringVar(3) = "123456789" Execute: StringVar(3,1,4) = "" "12356789" Results: StringVar(4) = StringVar(3) "123" But, StringVar(3) still = "12356789", so, StringVar(5) = StringVar(3,1,4+1) '"56789" StringVar(6) = StringVar(3) + 4 + StringVar(3,1,4+1) '"123456789" Some smart sensors send strings containing NULL characters. To manipulate a string that has NULL characters within it (in addition to being terminated with another NULL), use MoveBytes() instruction. 238