php循环

while

例子：

/* example 1 */
$a = 0;
while (true) {
    $a++;
    echo $a.'<br>';
    if($a >= 10){
        break; //打断循环
    }
}

/* example 2 */
$a = 0;
while ($a < 10) {
    $a++;
    echo $a.'<br>';

}

/* example 3 */
$arr = array("orange", "banana", "apple", "raspberry");
$i = 0;
while ($i < count($arr)) {
   $a = $arr[$i];
   echo $a .",";
   $i++;
}

/* example 4 */
$myArray=['aa','bb','cc','dd'];

while (list ($key, $val) = each ($myArray)) {
    echo "$key=>$val,";
}

do-while

例子：

$a=0;

do{
    $a++;
    echo $a;
}
while ($a < 10);

for

例子：

/* example 1 */

for ($i = 1; $i <= 10; $i++) {
    echo $i;
}

echo "<br>";

/* example 2 */

for ($i = 1; ; $i++) {
    if ($i > 10) {
        break;
    }
    echo $i;
}

echo "<br>";

/* example 3 */

$i = 1;
for (;;) {
    if ($i > 10) {
        break;
    }
    echo $i;
    $i++;
}

echo "<br>";

/* example 4 */

for ($i = 1, $j = 0; $i <= 10; $j += $i, print $i, $i++);

foreach

例子：

$arr = array(1, 2, 3, 4);

/* example 1 */
foreach ($arr as $value) {
	echo $value.'<br>';
}

/* example 2 */
foreach ($arr as $key => $val) {
    echo "$key=>$val,";
}