传递逗号分隔的键字符串并根据PHP中的键获取数组的值

Question

I am trying to get value from array and pass only comma separated key string and get same output without. Is it possible without using foreach statement. Please suggest me.

<?php
$str = "1,2,3";
$array = array("1"=>"apple", "2"=>"banana", "3"=>"orange");

$keyarray = explode(",",$str);
$valArr = array();
foreach($keyarray as $key){
   $valArr[] = $array[$key];
}
echo $valStr = implode(",", $valArr);    
?>    

Output : apple,banana,orange

Answer 1

Suggestion : Use separate row for each value, to better operation. Although you have created right code to get from Comma sparate key to Value from array , but If you need it without any loop, PHP has some inbuilt functions like array_insersect , array_flip to same output

$str = "1,2";
$arr1 = ["1"=>"test1","2"=>"test2","3"=>"test3"];
$arr2  = explode(",",$str);
echo implode(", ",array_flip(array_intersect(array_flip($arr1),$arr2)));

Live demo

Answer 2

Use array_intersect_key

$str = "1,2,3";
$array = array("1"=>"apple", "2"=>"banana", "3"=>"orange");

$keyarray = explode(",",$str);
echo implode(",", array_intersect_key($array, array_flip($keyarray)));

https://3v4l.org/gmcON

---

One liner:

echo implode(",", array_intersect_key($array, array_flip(explode(",",$str))));

A mess to read but a comment above can explain what it does.
It means you don't need the $keyarray

Answer 3

you can try using array_filter :

$str = "1,2,3";
$array = array("1"=>"apple", "2"=>"banana", "3"=>"orange");

$keyarray = explode(",",$str);

$filtered = array_filter($array, function($v,$k) use($keyarray){
    return in_array($k, $keyarray);
},ARRAY_FILTER_USE_BOTH);

print_r($filtered);

OUTPUT

Array
(
    [1] => apple
    [2] => banana
    [3] => orange
)

Answer 4

Another way could be using array_map() :

echo $valStr = implode(",", array_map(function ($i) use ($array) { return $array[$i]; }, explode(",", $str)));

Read it from bottom to top:

echo $valStr = implode(                 // 3. glue values
    ",",
    array_map(                          // 2. replace integers by fruits
        function ($i) use ($array) {
            return $array[$i];
        },
        explode(",", $str)              // 1. Split values
    )
);