for statement

PHP for loop

PHP for loop executes the code block a specified number of times.

PHP for loop

If you have determined in advance the number of times the script will run, you can use a for loop.

Syntax

for (init counter; test counter; increment counter) {
  code to be executed;
}

Parameters:

·     init counter: Initialize the value of the loop counter

·    Test counter:: Evaluate each loop iteration. If the value is TRUE, continue looping. If its value is FALSE, the loop ends.

·        increment counter: Increase the value of the loop counter

The following example shows the number from 0 to 10:

Example

<?php
for ($x=0; $x<=10; $x++) {
  echo "数字是：$x <br>";
}
?>

PHP foreach loop

The foreach loop only works on arrays and is used to iterate through each key/value pair in the array.

Syntax

foreach ($array as $value) {
  code to be executed;
}

Every time a loop iteration is performed, the value of the current array element will be assigned to the $value variable, and the array pointer will move one by one until the last array element is reached.

The following example demonstrates a loop that will output the values ​​of the given array ($colors):

Example

<?php
$colors = array("red","green","blue","yellow");
 
foreach ($colors as $value) {
  echo "$value <br>";
}
?>

for (expression indicates 1; expression indicates 2; expression indicates 3) {

The code segment that needs to be executed

#}

· Expressive 1 is initialized assignment and can assign multiple code at the same time.

·                       Expression 2 is evaluated before each loop starts. If the value is TRUE, the loop continues and the nested loop statement is executed. If the value is FALSE, the loop is terminated.

·    Expression 3 is evaluated after each loop.

· & LT;? PHP
· For ($ i = 1; $ i & lt; = 10; $ i ++) {
· Echo 'This is the first'. $ I. ' <br />';
·      }
·                                                                                                                                                     -------------------------------------------------- -------------------------------------------------- -------------------

Use a for loop to create a 9*9 multiplication table. ##//99 The multiplication table starts from 1, so declare a variable $i = 1 and make $i less than 10, that is, the maximum value is 9

<?PHP
     for($i=0,$j=10;$i<$j;$i++,$j--){
         echo $i.'---------'.$j.'<br />';
     }
 ?>

## The #foreach loop is used to traverse the array and can be used later when operating on the array.

Syntax

foreach ($array as $value)

Code to be executed;
}

Every time you loop, the value of the current array element will be assigned to the $value variable (the array pointer will move one by one), and when you loop next time, you will see the next value in the array.

<?php
?
>