Echo selected values from an associate array - php

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);
}

Related

How can I get only the first two elements of an array by using a foreach loop in PHP?

I have an array like this:
$aMyArray = array(
"bmw"=>"user1",
"audi"=>"user2",
"mercedes"=>"user3"
);
And I only want to show the first two elements bmw=>user1 and audi=>user2.
But I want it by using a foreach loop.
If you want the first 2 by name:
Using in_array (documentation) is what you looking for:
$aMyArray = array("bmw"=>"user1", "audi"=>"user2", "mercedes"=>"user3");
$valuesToPrint = array("bmw", "audi");
foreach($aMyArray as $key => $val) {
if (in_array($key, $valuesToPrint))
echo "Found: $key => $val" . PHP_EOL;
}
If you want the first 2 by index use:
init index at 0 and increment in each iteration as:
$aMyArray = array("bmw"=>"user1", "audi"=>"user2", "mercedes"=>"user3");
$i = 0;
foreach($aMyArray as $key => $val) {
echo "Found: $key => $val" . PHP_EOL;
if (++$i > 1)
break;
}
$counter = 1;
$max = 2;
foreach ($aMyArray as $key => $value) {
echo $key, "=>", $value;
$counter++;
if ($counter === $max) {
break;
}
}
It is important to break execution to avoid arrays of any size looping until the end for no reason.
<?php
$aMyArray = array(
"bmw"=>"user1",
"audi"=>"user2",
"mercedes"=>"user3"
);
reset($aMyArray);
echo key($aMyArray).' = '.current($aMyArray)."\n";
next($aMyArray);
echo key($aMyArray).' = '.current($aMyArray)."\n";
Easiest way:
$aMyArray=array("bmw"=>"user1","audi"=>"user2","mercedes"=>"user3");
$i=0;
foreach ($aMyArray as $key => $value) {
if($i<2)
{
echo $key . 'and' . $value;
}
$i++;
}
I know you're asking how to do it in a foreach, but another option is using array travelling functions current and next.
$aMyArray = array(
"bmw"=>"user1",
"audi"=>"user2",
"mercedes"=>"user3"
);
$keys = array_keys($aMyArray);
//current($array) will return the value of the current record in the array. At this point that will be the first record
$first = sprintf('%s - %s', current($keys), current($aMyArray)); //bmw - user1
//move the pointer to the next record in both $keys and $aMyArray
next($aMyArray);
next($keys);
//current($array) will now return the contents of the second element.
$second = sprintf('%s - %s', current($keys), current($aMyArray)); //audi - user2
You are looking for something like this
$aMyArray = array(
"bmw"=>"user1",
"audi"=>"user2",
"mercedes"=>"user3"
);
foreach($aMyArray as $k=>$v){
echo $v;
if($k=='audi'){
break;
}
}

What's Faster/More Efficient For Grabbing First 10 Elements In Array

I need the key, value, and index of the first 10 elements of my sorted associative array.
$top10pts = array_slice($toppoints, 0, 10);
foreach ($top10pts as $key => $val) {
echo "<tr><td>".(array_search($key, array_keys($top10pts))+1)."</td><td>".htmlentities($key)."</td><td>".$val."</td></tr>";
}
or
for ($i=0; $i<10; $i++) {
$val = array_slice($toppoints, $i, 1);
echo "<tr><td>".($i+1)."</td><td>".htmlentities(key($val))."</td><td>".$val[key($val)]."</td></tr>";
}
or another method?
Being new to PHP, both methods seem stupid and superfluous.
This is the best method that came to my mind.
$top10pts = array_slice($toppoints, 0, 10);
$i = 1;
foreach ($top10pts as $key => $val)
echo "<tr><td>".($i++)."</td><td>".htmlentities($key)."</td><td>".$val."</td></tr>";
Notice that, for more than 10 items, this method works better because it has no conditions in the loop. In interpreters such as php, it's usually better to use internal functions rather than doing the things yourself.
Similar to ernie's answer but you dont need array slice at all
$index = 0;
foreach ($top10pts as $key => $val) {
echo "<tr><td>".$index++."</td><td>".htmlentities($key)."</td><td>".$val."</td></tr>";
if($index >=10) break;
}
Since you sorted already, a foreach will iterate in order, so I'd use a modification of your first, getting rid of the array_search: . . .
$index = 0;
$top10pts = array_slice($toppoints, 0, 10);
foreach ($top10pts as $key => $val) {
echo "<tr><td>".$index."</td><td>".htmlentities($key)."</td><td>".$val."</td></tr>";
$index++;
}

Sorting arrays: second last

ksort ($votes);
foreach ($votes as $total => $contestant){
$ordervotes[]= $contestant;
}
echo "<li> And the winner is: {$ordervotes[4]}</li>";
echo "<li> And the loser is: {$ordervotes[0]}</li>";
echo "<li> {$ordervotes[1]} came second last</li>";
This works fine when none of the '$total's are the same, if they are the same i get an error code. I realise I could use the 'max/min' to get the first and last elements of the array, but how do i go about finding the second last?
Thank you
Joe
Why don't you try:
echo $votes[count($votes)-2];
You also don't need to populate another array with the same values - you can keep them in $votes. You might also want to look into sorting your array by value instead of by key (which I assume you're trying to do).
If you're expecting duplicate keys, you need to remodel the way you're storing your data. Consider using a multidimensional array:
$votes = array(
array('name'=>'John','vote'=>10),
array('name'=>'James','vote'=>11),
array('name'=>'Jimmy','vote'=>13),
);
You will be able to sort this array using this function and code:
// This function will sort your array
function aasort (&$array, $key) {
$sorter=array();
$ret=array();
reset($array);
foreach ($array as $ii => $va) {
$sorter[$ii]=$va[$key];
}
asort($sorter);
foreach ($sorter as $ii => $va) {
$ret[$ii]=$array[$ii];
}
$array=$ret;
}
// Sort the array by the 'vote' key
aasort($votes,"vote");
// Echo out the name of the second-last person
echo $votes[count($votes)-2]['name'];
Use this:
function secondMax($arr) {
$max = $second = 0;
$maxKey = $secondKey = null;
foreach($arr as $key => $value) {
if($value > $max) {
$second = $max;
$secondKey = $maxKey;
$max = $value;
$maxKey = $key;
} elseif($value > $secondMax) {
$second = $value;
$secondKey = $key;
}
}
return array($secondKey, $second);
}
Usage:
$second = secondMax($votes);
You can retrieve it by using the function count:
$ordervotes[ (count($ordervotes)-2) ]
// the array starts with index 0, so (count($ordervotes)-1) is the last element
I don't understand what is in your $votes variable ... How could you have multiple contestants with the same votes (and so, with the same key).
I think there is a mistake here.
You $votes should be like this :
$votes = array(
'contestant 1' => 8,
'contestant 2' => 12,
'contestant 3' => 3
);
Then order the array : sort($votes)
Finaly, get the second last : $votes[count($votes) - 2];

How to echo out the values of this array?

How to echo out the values individually of this array?
Array ( [0] => 20120514 [1] => My Event 3 )
so
echo $value[0]; etc
I have this so far:
foreach (json_decode($json_data_string, true) as $item) {
$eventDate = trim($item['date']);
// positive limit
$myarray = (explode(',', $eventDate, 2));
foreach ($myarray as $value) {
echo $value;
}
This echo's out the whole string no as an array. and if i do this?
echo $value[0};
Then I only get 2 characters of it??
The print_r :
Array ( [0] => 20120430 [1] => My Event 1 )
foreach ($array as $key => $val) {
echo $val;
}
Here is a simple routine for an array of primitive elements:
for ($i = 0; $i < count($mySimpleArray); $i++)
{
echo $mySimpleArray[$i] . "\n";
}
you need the set key and value in foreach loop for that:
foreach($item AS $key -> $value) {
echo $value;
}
this should do the trick :)
The problem here is in your explode statement
//$item['date'] presumably = 20120514. Do a print of this
$eventDate = trim($item['date']);
//This explodes on , but there is no , in $eventDate
//You also have a limit of 2 set in the below explode statement
$myarray = (explode(',', $eventDate, 2));
//$myarray is currently = to '20'
foreach ($myarray as $value) {
//Now you are iterating through a string
echo $value;
}
Try changing your initial $item['date'] to be 2012,04,30 if that's what you're trying to do. Otherwise I'm not entirely sure what you're trying to print.
var_dump($value)
it solved my problem, hope yours too.

How can I get the current array index in a foreach loop?

How do I get the current index in a foreach loop?
foreach ($arr as $key => $val)
{
// How do I get the index?
// How do I get the first element in an associative array?
}
In your sample code, it would just be $key.
If you want to know, for example, if this is the first, second, or ith iteration of the loop, this is your only option:
$i = -1;
foreach($arr as $val) {
$i++;
//$i is now the index. if $i == 0, then this is the first element.
...
}
Of course, this doesn't mean that $val == $arr[$i] because the array could be an associative array.
This is the most exhaustive answer so far and gets rid of the need for a $i variable floating around. It is a combo of Kip and Gnarf's answers.
$array = array( 'cat' => 'meow', 'dog' => 'woof', 'cow' => 'moo', 'computer' => 'beep' );
foreach( array_keys( $array ) as $index=>$key ) {
// display the current index + key + value
echo $index . ':' . $key . $array[$key];
// first index
if ( $index == 0 ) {
echo ' -- This is the first element in the associative array';
}
// last index
if ( $index == count( $array ) - 1 ) {
echo ' -- This is the last element in the associative array';
}
echo '<br>';
}
Hope it helps someone.
foreach($array as $key=>$value) {
// do stuff
}
$key is the index of each $array element
$i = 0;
foreach ($arr as $key => $val) {
if ($i === 0) {
// first index
}
// current index is $i
$i++;
}
The current index is the value of $key. And for the other question, you can also use:
current($arr)
to get the first element of any array, assuming that you aren't using the next(), prev() or other functions to change the internal pointer of the array.
You can get the index value with this
foreach ($arr as $key => $val)
{
$key = (int) $key;
//With the variable $key you can get access to the current array index
//You can use $val[$key] to
}
$key is the index for the current array element, and $val is the value of that array element.
The first element has an index of 0. Therefore, to access it, use $arr[0]
To get the first element of the array, use this
$firstFound = false;
foreach($arr as $key=>$val)
{
if (!$firstFound)
$first = $val;
else
$firstFound = true;
// do whatever you want here
}
// now ($first) has the value of the first element in the array
You could get the first element in the array_keys() function as well. Or array_search() the keys for the "index" of a key. If you are inside a foreach loop, the simple incrementing counter (suggested by kip or cletus) is probably your most efficient method though.
<?php
$array = array('test', '1', '2');
$keys = array_keys($array);
var_dump($keys[0]); // int(0)
$array = array('test'=>'something', 'test2'=>'something else');
$keys = array_keys($array);
var_dump(array_search("test2", $keys)); // int(1)
var_dump(array_search("test3", $keys)); // bool(false)
well since this is the first google hit for this problem:
function mb_tell(&$msg) {
if(count($msg) == 0) {
return 0;
}
//prev($msg);
$kv = each($msg);
if(!prev($msg)) {
end($msg);
print_r($kv);
return ($kv[0]+1);
}
print_r($kv);
return ($kv[0]);
}
based on #fabien-snauwaert's answer but simplified if you do not need the original key
$array = array( 'cat' => 'meow', 'dog' => 'woof', 'cow' => 'moo', 'computer' => 'beep' );
foreach( array_values( $array ) as $index=>$value ) {
// display the current index + value
echo $index . ':' . $value;
// first index
if ( $index == 0 ) {
echo ' -- This is the first element in the associative array';
}
// last index
if ( $index == count( $array ) - 1 ) {
echo ' -- This is the last element in the associative array';
}
echo '<br>';
}

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