PHP for loop
In this chapter you will learn:
- What is for loop
- for loop Syntax
- Example - for loop with
- Example - Infinite Loops
- Example - Loops Within Loops
Description
A for loop is made up of a declaration, a condition, and an action:
- declaration defines a loop-counter variable and sets it to a starting value;
- condition checks the loop-counter variable against a value;
- action changes the loop counter.
Syntax
The general syntax of a for loop is as follows:
for ( declaration; condition; action ) {
// Run this code /* j av a 2 s . c o m*/
}
// More code here
Example 1
Here is how a for loop looks in PHP:
<?php//from j a v a 2 s.co m
for ($i = 1; $i < 10; $i++) {
print "Number $i\n";
}
?>
The code above generates the following result.
As you can see, the for loop has the three parts separated by semicolons. In the declaration, we set the variable $i to 1.
For the condition, we have the loop execute if $i is less than 10.
Finally, for the action, we add 1 to the value of $i for every loop iteration.
Example 2
The following example has an infinite loop.
<?php//from jav a 2 s .com
for (;;) {
print "In loop!\n";
}
?>
Example 3
You can nest loops as you see fit, like this:
<?php/*from j av a 2s. c om*/
for ($i = 1; $i < 3; $i = $i + 1) {
for ($j = 1; $j < 3; $j = $j + 1) {
for ($k = 1; $k < 3; $k = $k + 1) {
print "I: $i, J: $j, K: $k\n";
}
}
}
?>
The code above generates the following result.
Next chapter...
What you will learn in the next chapter:
- What is a break statement
- Syntax for break statement
- Example - exit a for loop with break statement
- Example - Exit only one level of loop
- Example - exit more than one level with break statement