Merge an array with a string variable in PHP implode - php

Question

implode(',', $a);
I want to attach the $q variable in front of the $a so like this
implode(',', $q.$a);
But that doesn`t work. How can i put 2 variables in a implode function?
$a is an array with domain names like "com, org" and $q is the text (string) you type in before the domain names will appear.
I get the following error:
invalid argument passed in line..
Whole code:
$a = ['nl','net','com','co'];
$q = $_REQUEST["q"];
$domain = explode(".", $q);
$ext = #$domain[1] ?: ' ';
if (empty($ext)) {
echo implode(',',$a);
} else if (in_array($ext, $a)) {
echo $q;
} else {
$r = [];
foreach ($a as $x) {
if (strstr($x, $ext)) {
$r[] = $x;
}
}
echo (count($r)) ? implode(',',$r) : implode(',',$a);
}

Answer 1

If $a is an array and $q is the prefix string you can achieve that with 2 steps:
Add the prefix with:
$a = array("com", "co");
$q = "robot.";
foreach ($a as &$value)
$value = $q.$value;
Second, use the implode:
echo implode(',',$a);
output is:
robot.com,robot.co
Edited
I think this will be more suitable for you:
$a = array("com", "co", "org");
$q = "robot.c";
$arr = explode(".", $q);
$output = array();
foreach ($a as &$value) {
if (substr($value, 0, strlen($arr[1])) === $arr[1])
$output[]= $arr[0] . "." . $value;
}
echo implode(',',$output);
In this code you take the domain prefix and search for all domain name that may be fit for the prefix.
Notice that is this example we have domain org but he does not show up because your prefix is c

Answer 2

You need to add your $q before implode function. You can add your $q into your $a array using array_map function.
$array = array('com', 'org', 'net');
$q = 'test';
$array = array_map(function($value) {
$q= "test"; // you $q value goes here.
return $q.".".$value;
}, $array);
echo implode(',',$array);

Answer 3

Assuming that your business logic guarantees that $a is never empty, then here is the most direct, efficient, and concise technique...
Code: (Demo)
$a = ['nl', 'net', 'com', 'co'];
$q = 'example';
echo "$q." . implode(",$q.", $a);
Output:
example.nl,example.net,example.com,example.co
See how there is no need to loop or call any additional functions?
This basic technique of expanding the delimiting glue can be seen in other usages like:
echo '<tr><td>' . implode('</td><td>', $array) . '</td></tr>';
The idea is that you prepend what you need before the first value, then you declare the glue to be the characters that you need to occur after each value AND before the next value.

Answer 4

Merge an array with a string variable in PHP with the help of implode function
$a = array("com", "co");
$q = "robot.c";
$temp = explode(".",$q);
foreach ($a as $value)
echo $value = $temp[0].".".$value;