每3个迭代中断一次while循环

Question

我正在使用此PHP从0-9生成列表。

$counter = 0; 
WHILE ($counter < 10) 
{ 
  print "counter is now " . $counter . "<br>"; 
  $counter++; 
}

我想更改其工作方式。 每3次迭代 ，如果可能的话，我想将打印的文本包装在<div> 。

所以最终我的输出代码将是：

<div>
counter is now 0
counter is now 1
counter is now 2
</div>
<div>
counter is now 3
counter is now 4
counter is now 5
</div>
<div>
counter is now 6
counter is now 7
counter is now 8
</div>
<div>
counter is now 9
</div>

Answer 1

使用模数运算符，您可以每3次迭代拆分一次输出，但是您仍然需要检查可能生成空div块的limit

<?php

$counter = 0; 
$limit = 10;

print "<div>\n";

while ($counter < $limit) { 
  print "counter is now " . $counter . "<br>\n"; 

  if (++$counter % 3 === 0 && $counter < $limit) {
    print "</div>\n<div>\n";

  }
}
print "</div>\n";

Answer 2

使用模数来做

while($counter < 10) {
   if($counter % 3 == 0) {
       //Do something for the third row
   }
   $counter++;
}

Answer 3

尝试：

$counter = 0;
$block_count = 0;
echo "<div>";
while ($counter < 10) {
if ($block_count === 3) {
    echo "</div><div>";
    $block_count = 0;
}
  echo "counter is now " . $counter . "<br>";
  $block_count++;
  $counter++; 
}
echo "</div>";

Answer 4

我不知道php，但我认为逻辑是相同的：

$counter2 =0; //count to 10
$stopIteration =10;

WHILE($counter2<$stopIteration){ 
    print "<div>";
    $counter1 =0; //count to 3
    WHILE($counter1<3){
        print "counter is now".$counter2."<br>";
        $counter1++;
        $counter2++;
    }
    print "</div>"; 
} 

Answer 5

我发现，针对此类任务的最佳故障保护方法是将所有数据（在本例中为所有10个打印字符串）分组在数组中，而不是将此数组拆分为大块http://php.net/manual/en/function。 array-chunk.php ，然后您就可以使用这个新数组，因为它分成多个块，每个块不大于示例3。但是您的输出不会失败，因为模态仅在总计数时才起作用的元素模态为0，在这种情况下10个元素将失败，因为在最后一个循环中，模态语句将不起作用。

当没有除以3的元素总数时，这将添加故障保护。

$counter = 0; 
$arr = array();
WHILE ($counter < 10) 
{ 
  $arr[] =  "counter is now " . $counter . "<br>"; 
  $counter++; 
}

$arr = array_chunk($arr, 3);
foreach ($arr as $chunk) {
    //wrap each chunk into div
    echo "<div>"
    foreach ($chunk as $string) {
        //print your string here
     }
    echo "</div>"
}