Campbell CR3000 Micrologger, Руководство оператора

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Section 7. Installation
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7.7.19.3 String NULL Character
All strings are automatically NULL terminated. NULL is the same as 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.
String NULL Character Examples
Expression Comments Resul
t
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"
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.