Question

此代码会导致图像在页面中以“随机”方式显示。

<?php
$myImagesList = array (
    'image1.png',
    'image2.png',
    'image3.png',
    'image4.png'
);



shuffle ($myImagesList);
foreach ($myImagesList as $displayImagesAtRandomOrder) {
echo '<img src="/imagens/' . $displayImagesAtRandomOrder . '" width="200" height="40" border="0" />';
}
?>

示例：

image1.png image3.png image2.png image4.png

F5 reshesh page

image2.png image3.png image4.png image3.png

F5 reshesh page

image1.png image4.png image3.png image2.png

F5 reshesh page

image2.png image3.png image1.png image4.png

但是如何一次只显示两张图片？例如：

image1.png image3.png

F5 reshesh page

image3.png image2.png

F5 reshesh page

image2.png image4.png

F5 reshesh page

image3.png image1.png

Answer 1

一种简单的方法就是限制迭代

<?php
$myImagesList = array (
    'image1.png',
    'image2.png',
    'image3.png',
    'image4.png'
);

$count = 1; //set up our count, start at our first image
$imagesToShow = 2; //how many images we want to show



shuffle ($myImagesList);
foreach ($myImagesList as $displayImagesAtRandomOrder) {
    //if we have reached our count, let's break out of our loop
    if($count > $imagesToShow) { break; }
    echo '<img src="/imagens/' . $displayImagesAtRandomOrder . '" width="200" height="40" border="0" />';
    $count++; //increase our count each loop iteration
}
?>

Answer 2

在对它们进行洗牌后，您可以在数组中的前两个（0和1）项目中循环两次：

shuffle ($myImagesList);
for ($i=0; $i<2; $i++) {
echo '<img src="/imagens/' . $myImagesList[$i] . '" width="200" height="40" border="0" />';
}

Answer 3

使用for-loop代替foreach，只需2次迭代：

<?php

$myImagesList = array (
    'image1.png',
    'image2.png',
    'image3.png',
    'image4.png'
);

shuffle ($myImagesList);

for($index = 0; $index < 2; $index++){
    echo '<img src="/imagens/' . $myImagesList[$index] . '" width="200" height="40" border="0" />';
}

?>

如果您不知道两个关键字的区别：what are the difference between for loop & for each loop in php

Answer 4

$imageCounter = 0;
foreach ($myImagesList as $displayImagesAtRandomOrder) {
  $imageCounter++;
  echo '<img src="/imagens/' . $displayImagesAtRandomOrder . '" width="200"   height="40" border="0" />';
  if (!($imageCounter % 2)) break;
}

以上代码仅显示2张图片。您可以将该号码更改为您想要的任何号码。希望它有所帮助。

限制显示php的图像数量

4 个答案: