Php开关仅从字母表中选择几个字母

Question

我想让它只打印我设置的变量，但是从这里打印所有内容当我使用中断其打印仅用于A

<?php
$A=1;
$B=2;
$E=5;

switch($A OR $B OR $E)
{
    case 1:
    {
        printf("Letter A is first in alphabet <br>");
    }
    case 2:
    {
        printf("Letter B is second in alphabet <br>");
    }
    case 3:
    {
        printf("Letter C is third in alphabet <br>");
    }
    case 4:
    {
        printf("Letter D is fourth in alphabet <br>");
    }
    case 5:
    {
        printf("Letter E is fifth in alphabet <br>");
    }
}
?>

我尝试使用数组，但我不知道我是否使用过它，

<?php
$A= array(
    "A" => 1,
    "B" => 2,
    "E" => 5,
    );
switch($A)
{
    case 1:
    {
        printf("Letter A is first in alphabet <br>");
    }
    break;
    case 2:
    {
        printf("Letter B is second in alphabet <br>");
    }
    break;
    case 3:
    {
        printf("Letter C is third in alphabet <br>");
    }
    break;
    case 4:
    {
        printf("Letter D is fourth in alphabet <br>");
    }
    break;
    case 5:
    {
        printf("Letter E is fifth in alphabet <br>");
    }
    break;
}
?>

但是什么也没出现然后我尝试仅在数组中使用数字

<?php
$A=array(1,2,5);
switch($A)
{
    case 1:
    {
        printf("Letter A is first in alphabet <br>");
    }
    break;
    case 2:
    {
        printf("Letter B is second in alphabet <br>");
    }
    break;
    case 3:
    {
        printf("Letter C is third in alphabet <br>");
    }
    break;
    case 4:
    {
        printf("Letter D is fourth in alphabet <br>");
    }
    break;
    case 5:
    {
        printf("Letter E is fifth in alphabet <br>");
    }
    break;
}
?>

我不知道即时消息是否正确地使用了数组，因此我是否可以提前得到一些建议。我上学需要这个，我和我的大多数朋友都对此感到恐惧，希望这可以帮助您解决我的问题。