13. WMLScript Looping
Statements
Looping
statements are used to repeat the execution of a block of statements.
The looping continues or stops based on some conditions. The while
statement and the for statement are used for looping in
WMLScript.
13.1. while
Statement
WMLScript's
while statement is used to repeat the execution of a block of
statements while a condition is true. It has the following syntax:
while
(condition) { WMLScript statement(s) }
The
statement(s) enclosed in the curly brackets {} will be executed again
and again as long as condition is true. The loop stops when
condition evaluates to false or invalid. The curly brackets
can be omitted if there is only one statement in the while
loop. The following WMLScript example demonstrates how to use the
while statement:
var
counter = 0; var result = 0;
while (counter <
10) { result += 2; counter++; }
In
the above WMLScript example, the counter variable is first
initialized to 0. Every time the code inside the while loop is
executed, the value of counter is incremented by 1. After
executing the while loop for 10 times, the value of counter
becomes 10 and the expression "counter < 10" is false.
This quits the while loop. The WMLScript statement "result
+= 2;" has been executed 10 times totally. Hence, the result
variable contains the value 20 when the while loop stops.
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