shuffle（$ all）对我来说），我不知道为什么不适合你。要选三个，做：

  $ mars = array（'火星有多大？'，'火星有多少个月亮？ ？，火星有多远？，火星上的最高点是什么？）; 
 $ jupiter = array（木星有多大？，木星有多少个卫星？，木星有多远？，木星的最高点是什么？ 
 $ earth = array（地球有多大？，地球有多少个卫星？，地球有多远？，地球上的最高点是什么？ 
 $ sun = array（'太阳有多大？'，'太阳有多少个卫星'，'太阳有多远？''太阳的最高点是什么？ ）; 

 $ all = array（$ mars，$ jupiter，$ earth，$ sun）; 
 shuffle（$ all）; 

函数createList（$ a）
 {
 echo< ul>; 
 $ count = 1; 

 foreach（$ a as $ array）
 {
 $ questions = count（$ array）; 
 $ idquestion = rand（0，$ questions-1）; 
回显< li> 。 $ array [$ idquestion]。 &LT; /锂> 中; 
 if（$ count ++> = 3）{
 break; 
} 
} 
 echo< / ul>; 
} 

 createList（$ all）; 
 

break 提前终止循环。 p>

DEMO

In a previous question I didn't realize that I wouldn't be able to add in the rest of the changes myself, so here is what I'm working with. User webfix helped me get this:

$mars = array ('How big is Mars?', 'How many moons does Mars have?', 'How far away is Mars?', 'What is the highest point on Mars?');
$jupiter = array ('How big is Jupiter?', 'How many moons does Jupiter have?', 'How far away is Jupiter?', 'What is the highest point on Jupiter?');
$earth = array ('How big is Earth?', 'How many moons does Earth have?', 'How far away is Earth?', 'What is the highest point on Earth?');
$sun = array ('How big is the Sun?', 'How many moons does the Sun have?', 'How far away is the Sun?', 'What is the highest point on the Sun?');

$all = array($mars, $jupiter, $earth, $sun);

function createList($a)
{
echo "<ul>";    
foreach ($a as $array) 
    {
    $questions = count($array);
    $idquestion = rand(0, $questions-1);
    echo "<li>" . $array[$idquestion]  . "</li>";
    }
echo "</ul>";
}

createList($all);

I now want to add to this a randomization of the order of questions as well as a maximum of three (or any number to be changed later) questions spit out.

It currently will choose one of each question ($mars, $jupiter, $earth, $sun) and then make it into a list in that order. I want the order to be randomized and for only three of them to be chosen.

I tried to use "shuffle ($all)", but that didn't work and maybe we could use something like the "for ($i = 1; $i < 4; $i++)" to make it stop after picking three? Thanks.

shuffle($all) should work (it works for me), I don't know why it isn't for you. To pick three, do:

$mars = array ('How big is Mars?', 'How many moons does Mars have?', 'How far away is Mars?', 'What is the highest point on Mars?');
$jupiter = array ('How big is Jupiter?', 'How many moons does Jupiter have?', 'How far away is Jupiter?', 'What is the highest point on Jupiter?');
$earth = array ('How big is Earth?', 'How many moons does Earth have?', 'How far away is Earth?', 'What is the highest point on Earth?');
$sun = array ('How big is the Sun?', 'How many moons does the Sun have?', 'How far away is the Sun?', 'What is the highest point on the Sun?');

$all = array($mars, $jupiter, $earth, $sun);
shuffle($all);

function createList($a)
{
  echo "<ul>"; 
  $count = 1;

  foreach ($a as $array) 
    {
      $questions = count($array);
      $idquestion = rand(0, $questions-1);
      echo "<li>" . $array[$idquestion]  . "</li>";
      if ($count++ >= 3) {
        break;
      }
    }
  echo "</ul>";
}

createList($all);

break terminates a loop early.

DEMO