The while
statement executes an Expression and a Statement repeatedly until the
value of the Expression is false
.
WhileStatement:
while (
Expression)
Statement WhileStatementNoShortIf:
while (
Expression)
StatementNoShortIf
The Expression must have type boolean
, or a compile-time error occurs.
A while
statement is executed by first evaluating the Expression. If evaluation of the Expression completes abruptly for some reason, the while
statement completes abruptly for the same reason. Otherwise, execution continues by making a choice based on the resulting value:
true
, then the contained Statement is executed. Then there is a choice:
while
statement is executed again, beginning by re-evaluating the Expression.
false
, no further action is taken and the while
statement completes normally.
If the value of the Expression is false
the first time it is evaluated, then the
Statement is not executed.