Phonetics Sensaphone SCADA 3000, Руководство пользователя

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Arguments
condition
Numeric or string expression that is True or False . If
condition
is Null,
condition
is
treated as False .
statements
One or more statements that are repeated while or until condition is True .
Operators
Symbols used to execute mathematical operations and determine whether a particular condition
exists.
+ Adds two values
- Subtracts two values
* Multiplies two values
/ Divides two values and returns a floating point result
\ Divides two values and provides an integer result
Mod Finds the remainder of a division
^
Raises a number to the power of an exponent
Or Checks if one condition or another exists
And Checks if one condition and another exists
ASSIGNMENT - Symbol used to assign a numeric value.
= assigns a new value to a variable
COMPARATORS -Symbols used to compare numeric values to each other
< Less than
> Greater than
= Is equal to
<> Is not equal to
<= Less than or equal to
>= Greater than or equal to
COMMENTS -Text used to add notes to a program. Typically used to briefly explain what the
program or statement is doing. They may be used freely to make a program easier to under-
stand. Comments are ignored by the program. A comment is identified by a single quote at the
beginning of the line.
' comment
mONTH, DAY, YeAR, HOURS, mINUTeS, SeCONDS, & WeeKDAY
These variables represent the values from the real-time clock in your PC. They do not have to
be declared in a Dim statement. The variable names are as follows:
22-9
Chapter 22: Distributed Control using Visual Basic