How can I easily remove the last comma from an array? - php

Let's say I have this:
$array = array("john" => "doe", "foe" => "bar", "oh" => "yeah");
foreach($array as $i=>$k)
{
echo $i.'-'.$k.',';
}
echoes "john-doe,foe-bar,oh-yeah,"
How do I get rid of the last comma?

Alternatively you can use the rtrim function as:
$result = '';
foreach($array as $i=>$k) {
$result .= $i.'-'.$k.',';
}
$result = rtrim($result,',');
echo $result;

I dislike all previous recipes.
Php is not C and has higher-level ways to deal with this particular problem.
I will begin from the point where you have an array like this:
$array = array('john-doe', 'foe-bar', 'oh-yeah');
You can build such an array from the initial one using a loop or array_map() function. Note that I'm using single-quoted strings. This is a micro-optimization if you don't have variable names that need to be substituted.
Now you need to generate a CSV string from this array, it can be done like this:
echo implode(',', $array);

One method is by using substr
$array = array("john" => "doe", "foe" => "bar", "oh" => "yeah");
$output = "";
foreach($array as $i=>$k)
{
$output .= $i.'-'.$k.',';
}
$output = substr($output, 0, -1);
echo $output;
Another method would be using implode
$array = array("john" => "doe", "foe" => "bar", "oh" => "yeah");
$output = array();
foreach($array as $i=>$k)
{
$output[] = $i.'-'.$k;
}
echo implode(',', $output);

I don't like this idea of using substr at all, since it's the style of bad programming. The idea is to concatenate all elements and to separate them by special "separating" phrases. The idea to call the substring for that is like to use a laser to shoot the birds.
In the project I am currently dealing with, we try to get rid of bad habits in coding. And this sample is considered one of them. We force programmers to write this code like this:
$first = true;
$result = "";
foreach ($array as $i => $k) {
if (!$first) $result .= ",";
$first = false;
$result .= $i.'-'.$k;
}
echo $result;
The purpose of this code is much clearer, than the one that uses substr. Or you can simply use implode function (our project is in Java, so we had to design our own function for concatenating strings that way). You should use substr function only when you have a real need for that. Here this should be avoided, since it's a sign of bad programming style.

I always use this method:
$result = '';
foreach($array as $i=>$k) {
if(strlen($result) > 0) {
$result .= ","
}
$result .= $i.'-'.$k;
}
echo $result;

try this code after foreach condition then echo $result1
$result1=substr($i, 0, -1);

Assuming the array is an index, this is working for me. I loop $i and test $i against the $key. When the key ends, the commas do not print. Notice the IF has two values to make sure the first value does not have a comma at the very beginning.
foreach($array as $key => $value)
{
$w = $key;
//echo "<br>w: ".$w."<br>";// test text
//echo "x: ".$x."<br>";// test text
if($w == $x && $w != 0 )
{
echo ", ";
}
echo $value;
$x++;
}

this would do:
rtrim ($string, ',')

see this example you can easily understand
$name = ["sumon","karim","akash"];
foreach($name as $key =>$value){
echo $value;
if($key<count($name){
echo ",";
}
}

I have removed comma from last value of aray by using last key of array. Hope this will give you idea.
$last_key = end(array_keys($myArray));
foreach ($myArray as $key => $value ) {
$product_cateogry_details="SELECT * FROM `product_cateogry` WHERE `admin_id`='$admin_id' AND `id` = '$value'";
$product_cateogry_details_query=mysqli_query($con,$product_cateogry_details);
$detail=mysqli_fetch_array($product_cateogry_details_query);
if ($last_key == $key) {
echo $detail['product_cateogry'];
}else{
echo $detail['product_cateogry']." , ";
}
}

$foods = [
'vegetables' => 'brinjal',
'fruits' => 'orange',
'drinks' => 'water'
];
$separateKeys = array_keys($foods);
$countedKeys = count($separateKeys);
for ($i = 0; $i < $countedKeys; $i++) {
if ($i == $countedKeys - 1) {
echo $foods[$separateKeys[$i]] . "";
} else {
echo $foods[$separateKeys[$i]] . ", \n";
}
}
Here $foods is my sample associative array.
I separated the keys of the array to count the keys.
Then by a for loop, I have printed the comma if it is not the last element and removed the comma if it is the last element by $countedKeys-1.

Related

Echo selected values from an associate array

i dont want to echo the last two values in an associative array, couldn's figure it out, please help.
foreach($_POST as $key => $value){
echo $value;
}
This echoes all the values, i want to echo all but the last 2.
Just count the loops and dont print the value in the last two loops.
$i = 0;
foreach($_POST as $key => $value) {
$i++;
if($i != count($_POST) && $i != count($_POST)-1) {
echo $value;
}
}
It should work to slice the array before you loop it.
<?php
$newArray = array_slice( $_POST, 0, count($_POST)-2);
foreach( $newArray AS $key => $value ) {
echo $value;
}
If you want to keep your $key value, then set the 4th parameter to true to "preserve keys":
http://php.net/manual/en/function.array-slice.php
Maybe this is just an exercise, but I do want to note, in addition, that relying on the exact order of your POST'd elements sounds like a bad design idea that could lead to future problems.
I'd rather do this:
$a = array('a' => 'q','s' => 'w','d' => 'e','f' => 'r');
$arr_count = count($a) - 2;
$i = 1;
foreach($a as $k => $val){
echo $k.' - '.$val.PHP_EOL;
if ($i == $arr_count) break;
$i++;
}
Another alternative solution:
<?php
$tot=count($_POST)-2;
while ($tot--) {
// you can also retrieve the key using key($_POST);
echo current($_POST);
next($_POST);
}

PHP one array with and without explicit keys

I'm trying to figure out a better/cleaner way to have something like this in PHP:
// This will be parsed as the only argument in a function...
$params = array('Name', 'Age', 'Mail' => 'some#mail.com');
"Name" and "Age" are values with automatic keys (0 and 1, eg.), and "Mail" is a key with "some#mail.com" value:
[0] => 'Name',
[1] => 'Age',
['Mail'] => 'some#mail.com'
When running through it in a foreach loop, to have "Name" and "Age" as the actual parameters I'm using this:
foreach ($params as $k => $i) {
// This is the ugly part!
if (is_int($k)) {
$k = $i;
$i = false;
}
// To do something like this, for example...
$out = "";
if ($i) {
$out .= "<p>$k</p>\n";
} else {
$out .= "<p>$k<p>\n";
}
}
That will return something like this:
<p>Name</p>
<p>Age</p>
<p>Mail</p>
Is there a better way to do it?
Thanks in advance.
Edit #1: Elaborating the question: is there a clean PHP way to distinguish elements that have explicitly informed keys from the ones that have not in the same array?
You are right about the ugly part. It should be better when you use keys for all elements, and decide on the key name whether of not to use the mail link:
$params = array('name'=>'Name', 'age'=>'Age', 'mail'=>'some#mail.com');
foreach ($params as $k => $i) {
$out .= ($k == 'mail') ? '$k' : $k;
}
Why not just give name and age a key?
Or better yet, if you know that the params array will always be in this format, ditch the loop all together:
echo '<p>'.$params[0].'</p>';
echo '<p>'.$params[1].'</p>';
echo '<p>Mail</p>;
if (!is_int($k)) {
$out .= "<p>$k</p>\n";
} else {
$out .= "<p>$i<p>\n";
}
I found 2 solution for what I wanted:
1 - Sticking to the original approach, I could pass the arguments as follows:
my_function(['Name', 'Age', ['Mail' => 'a#mail.com']]);
or...
my_function(array('Name', 'Age', array('Mail' => 'a#mail.com')));
Using "is_array()" later on to distinguish the parameter's type:
if (is_array($i)) {
$p = current($i);
$c = key($i);
$out .= "<p>$c</p>\n";
} else {
$out .= "<p>$i<p>\n";
}
2 - But, changing my original paradigm, I found another option to parse a undefined number of arguments: the function "func_get_args()". My function would be called like this:
my_function('Name', 'Age', ['Mail' => 'a#mail.com']);
or...
my_function('Name', 'Age', array('Mail' => 'a#mail.com'));
Here is an example to create table rows:
function add_table_row() {
$args = func_get_args(); // returns an array of arguments...
$o = "<tr>\n";
foreach ($args as $value) {
if (is_array($value)) { // If the argument is an array...
$cellcont = key($value); // The contents is the key...
$param = current($value); // And the parameter is the value...
$o .= "<td $param>$cellcont</td>\n";
} else {
$o .= "<td>$value</td>\n";
}
}
$o .= "</tr>\n";
return $o;
}
Bottom line, both solutions uses "is_array" the same way, but the second one looks more clear, IMO.

converting array containing keys and values into string

I have an array it contains key and value. i would like to converting into a string.
array(
[business_type]=>'cafe'
[business_type_plural] => 'cafes'
[sample_tag]=>'couch'
[business_name]=>'couch cafe'
)
Expected Output:
business_type,cafe|business_type_plural,cafes|sample_tag,couch|business_name,couch cafe
NOTE:
I was searching in StackOverflow and found the below question and it has answer. I want exactly reverse one.
converting string containing keys and values into array
Try
$data = array();
foreach($arr as $key=>$value) {
$data[] = $key.','.$value;
}
echo implode('|',$data);
Another Solution:
function test_alter(&$item1, $key, $delimiter)
{
$item1 = "$key".$delimiter."$item1";
}
array_walk($arr, 'test_alter',',');
echo implode('|',$arr);
Use the foreach() function to go through the array and string the keys/values together...
Assuming your array is called $array
$result = "";
foreach($array as $key => $value){
$result .= $key . "," . $value . "|";
}
It's as simple as that.
EDIT - Thanks Nelson
After that, lost the last |
$result = rtrim($result, "|");
try this
$pieces=array();
foreach(array('key1'=>'val1', 'key2'=>'val2', 'key3'=>'val3') as $k=>$v)
{
$pieces[]=$k.','.$v;
}
echo implode('|', $pieces);

show only duplicate values from array without builtin function PHP

For example:
$arr = array(3,5,2,5,3,9);
I want to show only common elements i.e 3,5 as output.
Here's my attempt:
<?php
$arr = array(3,5,2,5,3,9);
$temp_array = array();
foreach($arr as $val)
{
if(isset($temp_array[$val]))
{
$temp_array[$val] = $val;
}else{
$temp_array[$val] = 0;
}
}
foreach($temp_array as $val2)
{
if($val2 > 0)
{
echo $val2 . ', ';
}
}
?>
--
Output --
3, 5,
Try the following:
$arr = array(3,5,2,5,3,9);
foreach($arr as $key => $val){
//remove the item from the array in order
//to prevent printing duplicates twice
unset($arr[$key]);
//now if another copy of this key still exists in the array
//print it since it's a dup
if (in_array($val,$arr)){
echo $val . " ";
}
}
Output:
3 5
Addition:
I guess that the reason you were asked to implement it yourself (without using built-in functions) was to avoid answers like:
$unique = array_unique($arr);
$dupes = array_diff_key( $arr, $unique );
$arrnew = array();
for($i=0;$i<count($arr);$i++)
{
for($j=$i+1;$j<count($arr);$j++)
{
if($arr[$i]==$arr[$j])
{
$arrnew[]=$arr[$j];
}
}
}

PHP foreach loop

I have the array example below that I am using to dynamically create an SQL query based on the options ticked in a form. The code below tests whether there is a value, if so, append it to the array:
if ($lookchild) { $val[]='lookchild'; }
if ($mentalcap) { $val[]='mentalcap'; }
if ($mentalheal) { $val[]='mentalheal'; }
if ($olderpeople) { $val[]='olderpeople'; }
if ($palcare) { $val[]='palcare'; }
I am then looping through the array and adding the rest of the SQL statement:
foreach ($val as $r){
echo $r.'=1 AND ';
}
This produces:
olderpeople=1 AND palcare=1 AND lookchild=1 AND
When the loop reaches the last entry, I don't want it to append the AND to it as the SQL statement needs to close after that point.
How I want it to complete:
olderpeople=1 AND palcare=1 AND lookchild=1
Implode
In these situations you can use implode
It 'glues' an array together.
implode ( string $glue , array
$pieces )
Example:
echo implode('=1 AND ', $val);
echo '=1';
A common trick is to use 'WHERE 1=1' then you can append ' AND foo = bar' without a syntax error.
WHERE 1=1 AND olderpeople=1 AND palcare=1 AND lookchild=1
This is what implode() is for:
$result = array();
foreach ($val as $r){
$result[] = "$r=1";
}
$result = implode($result, ' AND ');
Live Example
Just don't print the AND for the last value of the foreach loop. Here is the code to use:
foreach ($val as $r){
echo $r.'=1';
if (next($val)) {
echo ' AND ';
}
}
use the implode function
$sql = implode("=1 AND ", $array)."=1";
and you wont have to use a for loop :)
Instead on assigning palcare to $val[], assign $val[] = "palcare = 1" etc. Them
implode(" AND ", $val);
Try this :
$isFirst = true;
foreach ($val as $r){
if(!$isFirst){
echo ' AND ';
}else{
$isFirst = false;
}
echo $r.'=1';
}
I would remove the last 4 characters of the string with:
$r = '';
foreach ($val as $r){
$r.'=1 AND ';
}
$r = substr($r, 0, -4);
echo $r;
Checkout http://ca3.php.net/manual/en/function.substr.php, quick and easy
If you have to do it with a foreach (and for some reason you cant use implode, which is a good suggestion) you will need a way to keep track of where you are.
I thought to add the "AND" before anything but the first item, instead of adding it after anything but the last item, something like this:
$sqlwhere = "";
foreach ($val as $r){
if($sqlwhere ==""){
$sqlwhere = $r;
}
else {
$sqlwhere .= " AND " . $sqlwhere;
}
}
echo $sqlwhere;
I used a varable instead of just echoing it out too, which I find useful in complicated sql statements anyway.
Use implode. But if for some reason you need to loop (such as you need to do more logic than just joining the strings), use a separator approach:
$seperator = '';
$result = '';
foreach ($array as $value) {
// .. Do stuff here
$result .= $seperator . $value;
$seperator = ' AND ';
}
The benefit is both brevity and flexibility without checking conditions all the time...
Since you are using an array, you can also use count to figure out how many are in the array and if you are on the last item, don't append the 'AND'.
$result = array();
$totalcount = count($val);
$currentCount = 0;
foreach ($val as $r){
$currentCount ++;
if ($currentCount != $totalcount){$result[] = "$r=1 AND ";}else{$result[] = "$r=1";}
}

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