Campbell CR850, Руководство оператора

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Section 7. Installation
239
7.8.13.2 String Concatenation
Concatenation is the building of strings from other strings ("abc123"), characters
("a" or
chr() ), numbers, or variables.
Table 39. String Concatenation Examples
Expression Comments Result
Str(1) = 5.4 + 3 + " Volts"
Add floats, concatenate strings
"8.4 Volts"
Str(2) = 5.4 & 3 & " Volts" Concatenate floats and strings "5.43 Volts"
Lng(1) = "123" Convert string to long 123
Lng(2) = 1+2+"3"
Add floats to string / convert to long
33
Lng(3) = "1"+2+3 Concatenate string and floats 123
Lng(4) = 1&2&"3"
Concatenate floats and string
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) = "" "123<NULL>56789"
Results:
StringVar(4) = StringVar(3) "123"
But,
StringVar(3) still = "123<NULL>56789",
so,
StringVar(5) = StringVar(3,1,4+1)
'"56789"
StringVar(6) = StringVar(3) + 4 + StringVar(3,1,4+1)
'"123456789"