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Php 将foreach循环更改为for循环_Php_Loops_For Loop_Foreach - Fatal编程技术网

Php 将foreach循环更改为for循环

Php 将foreach循环更改为for循环,php,loops,for-loop,foreach,Php,Loops,For Loop,Foreach,我对PHP很陌生。如何将这个foreach循环更改为仅循环两次 <?php foreach($results as $row): ?> 试试这段代码,您只需要一个计数器变量,从零开始初始化计数器变量,并在每次迭代后递增它 <?php $counter = 0; foreach($results as $row) { //your code if($counter == 1) {

我对PHP很陌生。如何将这个foreach循环更改为仅循环两次

<?php 

foreach($results as $row):

?>

试试这段代码,您只需要一个计数器变量,从
零开始初始化计数器变量,并在每次迭代后递增它

<?php 
    $counter = 0; 
    foreach($results as $row) {
         //your code
         if($counter == 1)
         {
              break;
         }
         $counter++;   
    }

    ?>

您可以迭代到数组的大小,也可以迭代到两个数组中较小的2个

<?php 
$maxInd = min(2, count($results);
for ($i = 0; $i < $maxInd; ++$i) {
     $row =  $results[$i];
     // Do something interesting with $row
}
?>


但这仅适用于集合。有些示例(例如生成器)必须使用foreach

您需要一个计数器变量,您可以简单地递增并检查它是否等于2,如果是,则断开循环。然后使用for loop来实现这一点。请自己尝试一下,如果尝试,什么都不会爆炸,这是最好的学习方法。欢迎@jord49:)
<?php 

for ($i = 0, $count = count($results); $i < $count; ++$i) {
   var_dump($results[$i]);
   // or assign it to $result variable
   $result = $results[$i];
}

?>