Question

我有一阵列数据,我想用每个表(数据为美元细目)。 Th是,我想在内部印制以前和下一期内容。与此类似:

$data = array(1,2,3,4,5,6,7,8);

// foreach result should look like this
8,1,2
1,2,3
2,3,4
3,4,5
4,5,6
5,6,7
6,7,8
7,8,1

Answer 1

你可以:

$data = array (1,2,3,4,5,6,7,8);
$count = count ($data);
foreach ($data as $key => $current)
{
  if (($key - 1) < 0)
  {
    $prev = $data[$count - 1];
  }
  else
  {
    $prev = $data[$key - 1];
  }

  if (($key + 1) > ($count - 1))
  {
    $next = $data[0];
  }
  else
  {
    $next = $data[$key + 1];
  }

echo $prev .  ,   . $current .  ,   . $next . "
";

或者,如果简洁是一个问题:

$count = count ($data);
foreach ($data as $i => $current)
{
  $prev = $data[(($i - 1) < 0) ? ($count - 1) : ($i - 1)];
  $next = $data[(($i + 1) > ($count - 1)) ? 0 : ($i + 1)];

  echo $prev .  ,  . $current .  ,  . $next . "
";
}

Answer 2

<?php

$data = array(1,2,3,4,5,6,7,8);
$count = count($data);

foreach($data as $index => $number)
{
  $previous = $data[($count+$index-1) % $count]; //  $count+...  avoids problems
                                                 // with modulo on negative numbers in PHP
  $current = $number;
  $next = $data[($index+1) % $count];

  echo $previous.", ".$current.", ".$next."
";
}

关于负数的模块:

Answer 3

不同结果:

<?php
$data = range(1,16);
$count=count($data);
$ret=  ;

for($i=0;$i<$count;$i++){
    $ret.=($i==0)?$data[$count-1]. , :$data[$i-1]. , ;
    $ret.=$data[$i]. , ;
    $ret.=($i+1>=$count)?$data[$count-$i-1]:$data[$i+1]. <br> ;
}
echo $ret;
?>
Result:
16,1,2
1,2,3
2,3,4
3,4,5
4,5,6
5,6,7
6,7,8
7,8,9
8,9,10
9,10,11
10,11,12
11,12,13
12,13,14
13,14,15
14,15,16
15,16,1

友情链接