Campbell CR800 Spécifications télécharger pdf (Page 261)

Section 9. Program Control Instructions

contains only processing tasks, these tasks can run in conjunction with the

main scan.

While…Wend

The While…Wend instructions are used to executes a series of statements in a

loop as long as a given condition is true.

Syntax

While Condition

[StatementBlock]

Wend

Remarks

While…Wend loops can be nested.

The While...Wend statement has the following parameters:

While The While statement begins the While...Wend loop control

structure.

Condition The Condition is any expression that can be evaluated True

(nonzero) or False (0 and Null). If Condition is true, all

statements in StatementBlock are executed until the Wend

statement is encountered. Control then returns to the While

statement and Condition is again checked. If Condition is

still true, the process is repeated. If Condition it is not True,

execution resumes with the statement following the Wend

statement.

StatementBlock The StatementBlock is the portion of the program that

should be repeated until the loop is terminated. These

instructions lie between the While and Wend statements.

Wend The Wend statement ends the While...Wend control

structure.

The Do...Loop provides another way to perform looping.

NOTE

While...Wend Statement Example

This example creates a While...Wend that is exited only if Reply is within a

range.

Dim Reply 'Declare variable.

While Reply < 90

Reply = Reply + 1

Wend

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Campbell CR800 Spécifications Page 261