while loops are the simplest
type of loop in PHP. They behave just like their C
counterparts. The basic form of a
while statement is:
The meaning of a while
statement is simple. It tells PHP to execute the nested
statement(s) repeatedly, as long as the
while expression evaluates to
TRUE. The value of the expression is checked each
time at the beginning of the loop, so even if this value
changes during the execution of the nested statement(s),
execution will not stop until the end of the iteration (each
time PHP runs the statements in the loop is one iteration).
Sometimes, if the while expression
evaluates to FALSE from the
very beginning, the nested statement(s) won't even be run
once.
Like with the if statement, you
can group multiple statements within the same while loop by surrounding a group of
statements with curly braces, or by using the alternate
syntax:
The following examples are identical, and both print
numbers from 1 to 10:
/* example 1 */ $i = 1; while ($i = 10) { print $i++; /* the printed value would be $i before the increment (post-increment) */ } /* example 2 */ $i = 1; while ($i = 10): print $i; $i++; endwhile; |