PHP if in array, do something with the value - php

I am trying to check if a value is in an array. If so, grab that array value and do something with it. How would this be done?
Here's an example of what I'm trying to do:
$the_array = array("buejcxut->10", "jueofi31->20", "nay17dtt->30");
if (in_array('20', $the_array)) {
// If found, assign this value to a string, like $found = 'jueofi31->20'
$found_parts = explode('->', $found);
echo $found_parts['0']; // This would echo "jueofi31"
}

This should do it:
foreach($the_array as $key => $value) {
if(preg_match("#20#", $value)) {
$found_parts = explode('->', $value);
}
echo $found_parts[0];
}
And replace "20" by any value you want.

you might be better off checking it in a foreach loop:
foreach ($the_array as $key => $value) {
if ($value == 20) {
// do something
}
if ($value == 30) {
//do something else
}
}
also you array definitition is strange, did you mean to have:
$the_array = array("buejcxut"=>10, "jueofi31"=>20, "nay17dtt"=>30);
using the array above the $key is the element key (buejcxut, jueofi31, etc) and $value is the value of that element (10, 20, etc).

Here's an example of how you can search the values of arrays with Regular Expressions.
<?php
$the_array = array("buejcxut->10", "jueofi31->20", "nay17dtt->30");
$items = preg_grep('/20$/', $the_array);
if( isset($items[1]) ) {
// If found, assign this value to a string, like $found = 'jueofi31->20'
$found_parts = explode('->', $items[1]);
echo $found_parts['0']; // This would echo "jueofi31"
}
You can see a demo here: http://codepad.org/XClsw0UI

if you want to define an indexed array it should be like this:
$my_array = array("buejcxut"=>10, "jueofi31"=>20, "nay17dtt"=>30);
then you can use in_array
if (in_array("10", $my_array)) {
echo "10 is in the array";
// do something
}

Related

How to get index of array of object without using loop in PHP

I need to get index of from array of objects without using loop as per the key name using PHP. Here I am explaining my code below.
$arr = array(array("name"=>"Jack","ID"=>10),array("name"=>"Jam","ID"=>11),array("name"=>"Joy","ID"=>12));
$key = array_search('Jack', $arr);
echo $key;exit;
Here my code does not give any output. By using some key name I need the index of that object present inside array and also I dont want to use any loop. I need Is ther any PHP in build method so that I can get the result directly.
$arr = array(array("name"=>"Jack","ID"=>10),array("name"=>"Jam","ID"=>11),array("name"=>"Joy","ID"=>12));
function myfunction($v){return $v['name'];}
echo array_search('Jack', array_map( 'myfunction', $arr ));
<?php
$arr = array(array("name"=>"Jack","ID"=>10),array("name"=>"Jam","ID"=>11),array("name"=>"Joy","ID"=>12));
//calling function searchByName
$key = searchByName('Jasck',$arr);
if($key != '-1'){
print_r($arr[$key]);
}else{
echo "No match found";
}
//function to chek if the name is there or not.
function searchByName($name, $array) {
foreach ($array as $key => $val) {
if ($val['name'] == $name) {
return $key;
}
}
return '-1';
}
sandbox

PHP array_key_exists key LIKE string, is it possible?

I've done a bunch of searching but can't figure this one out.
I have an array like this:
$array = array(cat => 0, dog => 1);
I have a string like this:
I like cats.
I want to see if the string matches any keys in the array. I try the following but obviously it doesn't work.
array_key_exists("I like cats", $array)
Assuming that I can get any random string at a given time, how can I do something like this?
Pseudo code:
array_key_exists("I like cats", *.$array.*)
//The value for cat is "0"
Note that I want to check if "cat" in any form exists. It can be cats, cathy, even random letter like vbncatnm. I am getting the array from a mysql database and I need to know which ID cat or dog is.
You can use a regex on keys. So, if any words of your string equal to the key, $found is true. You can save the $key in the variable if you want. preg_match function allows to test a regular expression.
$keys = array_keys($array);
$found = false;
foreach ($keys as $key) {
//If the key is found in your string, set $found to true
if (preg_match("/".$key."/", "I like cats")) {
$found = true;
}
}
EDIT :
As said in comment, strpos could be better! So using the same code, you can just replace preg_match:
$keys = array_keys($array);
$found = false;
foreach ($keys as $key) {
//If the key is found in your string, set $found to true
if (false !== strpos("I like cats", $key)) {
$found = true;
}
}
This should help you achieve what you're trying to do:
$array = array('cat' => 10, 'dog' => 1);
$findThis = 'I like cats';
$filteredArray = array_filter($array, function($key) use($string){
return strpos($string, $key) !== false;
}, ARRAY_FILTER_USE_KEY);
I find that using the array_filter function with a closure/anonymous function to be a much more elegant way than a foreach loop because it maintains one level of indentation.
You could do using a preg_match with the value not in array but in search criteria
if(preg_match('~(cat|dog)~', "I like cats")) {
echo 'ok';
}
or
$criteria = '~(cat|dog)~';
if (preg_match($criteria, "I like cats")) {
echo 'ok';
}
Otherwise you could use a foreach on your array
foreach($array as $key => $value ) {
$pos = strpos("I like cats", $key);
if ($pos > 0) {
echo $key . ' '. $value;
}
}

Resetting position of items in array PHP

I have a string of 7 numbers in an array looks like 4,1,2,56,7,9,10 however sometimes these elements are empty ,,,56,7,9,10 for example. What I would like to do is reorder the array so it looks like 56,7,9,10,,,
try this:
$null_counter = 0;
foreach($array as $key => $val) {
if($val == null) {
$null_counter++;
unset($array[$key]);
}
}
for($x=1;$x<=$null_counter;$x++) {
$array[] = null;
}
Use unset in loop to remove null value and shift the values Up.
foreach($yourarray as $key=>$val )
{
if($yourarray[$key] == '')
{
unset($yourarray[$key]);
}
}

PHP - Grab the first element using a foreach

Wondering what would be a good method to get the first iteration on a foreach loop.
I want to do something different on the first iteration.
Is a conditional our best option on these cases?
Yes, if you are not able to go through the object in a different way (a normal for loop), just use a conditional in this case:
$first = true;
foreach ( $obj as $value )
{
if ( $first )
{
// do something
$first = false;
}
else
{
// do something
}
// do something
}
Even morer eleganterer:
foreach($array as $index => $value) {
if ($index == 0) {
echo $array[$index];
}
}
That example only works if you use PHP's built-in array append features/function or manually specify keys in proper numerical order.
Here's an approach that is not like the others listed here that should work via the natural order of any PHP array.
$first = array_shift($array);
//do stuff with $first
foreach($array as $elem) {
//do stuff with rest of array elements
}
array_unshift($array, $first); //return first element to top
You can simply add a counter to the start, like so:
$i = 0;
foreach($arr as $a){
if($i == 0) {
//do ze business
}
//the rest
$i++;
}
I saw this solution on a blog post in my search result set that brought up this post and I thought it was rather elegant. Though perhaps a bit heavy on processing.
foreach ($array as $element)
{
if ($element === reset($array))
echo 'FIRST ELEMENT!';
if ($element === end($array))
echo 'LAST ELEMENT!';
}
Do note there is also a warning on the post that this will only work if the array values are unique. If your last element is "world" and some random element in the middle is also "world" last element will execute twice.
hm
<?php
$i = 0;
foreach($ar as $sth) {
if($i++ == 0) {
// do something
}
// do something else
}
more elegant.
first = true
foreach(...)
if first
do stuff
first = false
This is also works
foreach($array as $element) {
if ($element === reset($array))
echo 'FIRST ELEMENT!';
if ($element === end($array))
echo 'LAST ELEMENT!';
}
foreach($array as $element) {
if ($element === reset($array))
echo 'FIRST ELEMENT!';
if ($element === end($array))
echo 'LAST ELEMENT!';
}
Here's an example that does not use foreach loop
<?php
// A sample indexed array
$cities = array("London", "Paris", "New York");
echo $cities[0]; // Outputs: London
// A sample associative array
$fruits = array("a" => "Apple", "b" => "Ball", "c" => "Cat");
echo array_values($fruits)["0"]; // Outputs: Apple
?>
What about using key() native php function? which should work fine with all kind of arrays (indexed, associative ) as it will always return the first key no matter if its inside or outside the loop.
$array = array(
'One' => 'value',
'Two' => 'value-2',
'Three' => 'value-3',
);
foreach ( $array as $index => $key ) {
if ( key( $array ) ) {
/**Do something with the first key*/
} else {
/**Do something else*/
}
}
if it indexed array, you have many options you can go through,
for me using counter is always fine and get the correct result all the time.
$array = array(
'One',
'Two',
'Three',
);
$i = 0;
foreach ( $array as $index => $key ) {
if ( $array[ $i ] ) {
/**Do something with the first key*/
} else {
/**Do something else*/
$i++;
}
}
Both should work fine with $key => $value loop and it will only return the first key.
Also I would like to add something, You can always archive your target in scripting with hundreds of different way, Its all about the way you want to use in this situation.

Find the last element of an array while using a foreach loop in PHP

I am writing a SQL query creator using some parameters. In Java, it's very easy to detect the last element of an array from inside the for loop by just checking the current array position with the array length.
for(int i=0; i< arr.length;i++){
boolean isLastElem = i== (arr.length -1) ? true : false;
}
In PHP they have non-integer indexes to access arrays. So you must iterate over an array using a foreach loop. This becomes problematic when you need to take some decision (in my case to append or/and parameter while building query).
I am sure there must be some standard way of doing this.
How do you solve this in PHP?
It sounds like you want something like this:
$numItems = count($arr);
$i = 0;
foreach($arr as $key=>$value) {
if(++$i === $numItems) {
echo "last index!";
}
}
That being said, you don't -have- to iterate over an "array" using foreach in php.
You could get the value of the last key of the array using end(array_keys($array)) and compare it to the current key:
$last_key = end(array_keys($array));
foreach ($array as $key => $value) {
if ($key == $last_key) {
// last element
} else {
// not last element
}
}
Note: This doesn't work because calling next() advances the array pointer, so you're skipping every other element in the loop
why so complicated?
foreach($input as $key => $value) {
$ret .= "$value";
if (next($input)==true) $ret .= ",";
}
This will add a , behind every value except the last one!
When toEnd reaches 0 it means it is at the last iteration of the loop.
$toEnd = count($arr);
foreach($arr as $key=>$value) {
if (0 === --$toEnd) {
echo "last index! $value";
}
}
The last value is still available after the loop, so if you just want to use it for more stuff after the loop this is better:
foreach($arr as $key=>$value) {
//something
}
echo "last index! $key => $value";
If you do not want to treat the last value as special inside loops. This should be faster if you have large arrays. (If you reuse the array after the loop inside the same scope you have to "copy" the array first).
//If you use this in a large global code without namespaces or functions then you can copy the array like this:
//$array = $originalArrayName; //uncomment to copy an array you may use after this loop
//end($array); $lastKey = key($array); //uncomment if you use the keys
$lastValue = array_pop($array);
//do something special with the last value here before you process all the others?
echo "Last is $lastValue", "\n";
foreach ($array as $key => $value) {
//do something with all values before the last value
echo "All except last value: $value", "\n";
}
//do something special with the last value here after you process all the others?
echo "Last is $lastValue", "\n";
And to answer your original question "in my case to append or/and parameter while building query"; this will loop over all the values, then join them together to a string with " and " between them but not before the first value or after the last value:
$params = [];
foreach ($array as $value) {
$params[] = doSomething($value);
}
$parameters = implode(" and ", $params);
There are already many answers, but it's worth to look into iterators as well, especially as it has been asked for a standard way:
$arr = range(1, 3);
$it = new CachingIterator(new ArrayIterator($arr));
foreach($it as $key => $value)
{
if (!$it->hasNext()) echo 'Last:';
echo $value, "\n";
}
You might find something that does work more flexible for other cases, too.
One way could be to detect if the iterator has next. If there is no next attached to the iterator it means you are in the last loop.
foreach ($some_array as $element) {
if(!next($some_array)) {
// This is the last $element
}
}
SINCE PHP 7.3 :
You could get the value of the last key of the array using array_key_last($array) and compare it to the current key:
$last_key = array_key_last($array);
foreach ($array as $key => $value) {
if ($key == $last_key) {
// last element
} else {
// not last element
}
}
to get first and last element from foreach array
foreach($array as $value) {
if ($value === reset($array)) {
echo 'FIRST ELEMENT!';
}
if ($value === end($array)) {
echo 'LAST ITEM!';
}
}
So, if your array has unique array values, then determining last iteration is trivial:
foreach($array as $element) {
if ($element === end($array))
echo 'LAST ELEMENT!';
}
As you see, this works if last element is appearing just once in array, otherwise you get a false alarm. In it is not, you have to compare the keys (which are unique for sure).
foreach($array as $key => $element) {
end($array);
if ($key === key($array))
echo 'LAST ELEMENT!';
}
Also note the strict coparision operator, which is quite important in this case.
Don't add a comma after the last value:
The array:
$data = ['lorem', 'ipsum', 'dolor', 'sit', 'amet'];
The function:
$result = "";
foreach($data as $value) {
$resut .= (next($data)) ? "$value, " : $value;
}
The result:
print $result;
lorem, ipsum, dolor, sit, amet
You can still use that method with associative arrays:
$keys = array_keys($array);
for ($i = 0, $l = count($array); $i < $l; ++$i) {
$key = $array[$i];
$value = $array[$key];
$isLastItem = ($i == ($l - 1));
// do stuff
}
// or this way...
$i = 0;
$l = count($array);
foreach ($array as $key => $value) {
$isLastItem = ($i == ($l - 1));
// do stuff
++$i;
}
Assuming you have the array stored in a variable...
foreach($array as $key=>$value)
{
echo $value;
if($key != count($array)-1) { echo ", "; }
}
If you need to do something for every element except either the first or the last and only if there is more than one element in the array, I prefer the following solution.
I know there are many solutions above and posted months/one year before mine, but this is something I feel is fairly elegant in its own right. The check every loop is also a boolean check as opposed to a numeric "i=(count-1)" check, which may allow for less overhead.
The structure of the loop may feel awkward, but you can compare it to the ordering of thead (beginning), tfoot (end), tbody (current) in HTML table tags.
$first = true;
foreach($array as $key => $value) {
if ($first) {
$first = false;
// Do what you want to do before the first element
echo "List of key, value pairs:\n";
} else {
// Do what you want to do at the end of every element
// except the last, assuming the list has more than one element
echo "\n";
}
// Do what you want to do for the current element
echo $key . ' => ' . $value;
}
For instance, in web development terms, if you want to add a border-bottom to every element except the last in an unordered list (ul), then you can instead add a border-top to every element except the first (the CSS :first-child, supported by IE7+ and Firefox/Webkit supports this logic, whereas :last-child is not supported by IE7).
You can feel free to reuse the $first variable for each and every nested loop as well and things will work just fine since every loop makes $first false during the first process of the first iteration (so breaks/exceptions won't cause issues).
$first = true;
foreach($array as $key => $subArray) {
if ($first) {
$string = "List of key => value array pairs:\n";
$first = false;
} else {
echo "\n";
}
$string .= $key . '=>(';
$first = true;
foreach($subArray as $key => $value) {
if ($first) {
$first = false;
} else {
$string .= ', ';
}
$string .= $key . '=>' . $value;
}
$string .= ')';
}
echo $string;
Example output:
List of key => value array pairs:
key1=>(v1_key1=>v1_val1, v1_key2=>v1_val2)
key2=>(v2_key1=>v2_val1, v2_key2=>v2_val2, v2_key3=>v2_val3)
key3=>(v3_key1=>v3_val1)
This should be the easy way to find the last element:
foreach ( $array as $key => $a ) {
if ( end( array_keys( $array ) ) == $key ) {
echo "Last element";
} else {
echo "Just another element";
}
}
Reference : Link
I have a strong feeling that at the root of this "XY problem" the OP wanted just implode() function.
As your intention of finding the EOF array is just for the glue. Get introduced to the below tactic. You need not require the EOF:
$given_array = array('column1'=>'value1',
'column2'=>'value2',
'column3'=>'value3');
$glue = '';
foreach($given_array as $column_name=>$value){
$where .= " $glue $column_name = $value"; //appending the glue
$glue = 'AND';
}
echo $where;
o/p:
column1 = value1 AND column2 = value2 AND column3 = value3
How about using "end"?
http://php.net/manual/en/function.end.php
It sounds like you want something like this:
$array = array(
'First',
'Second',
'Third',
'Last'
);
foreach($array as $key => $value)
{
if(end($array) === $value)
{
echo "last index!" . $value;
}
}
$array = array("dog", "rabbit", "horse", "rat", "cat");
foreach($array as $index => $animal) {
if ($index === array_key_first($array))
echo $animal; // output: dog
if ($index === array_key_last($array))
echo $animal; // output: cat
}
you can do a count().
for ($i=0;$i<count(arr);$i++){
$i == count(arr)-1 ? true : false;
}
or if you're looking for ONLY the last element, you can use end().
end(arr);
returns only the last element.
and, as it turns out, you CAN index php arrays by integers. It's perfectly happy with
arr[1];
You could also do something like this:
end( $elements );
$endKey = key($elements);
foreach ($elements as $key => $value)
{
if ($key == $endKey) // -- this is the last item
{
// do something
}
// more code
}
I kinda like the following as I feel it is fairly neat. Let's assume we're creating a string with separators between all the elements: e.g. a,b,c
$first = true;
foreach ( $items as $item ) {
$str = ($first)?$first=false:", ".$item;
}
Here's my solution:
Simply get the count of your array, minus 1 (since they start in 0).
$lastkey = count($array) - 1;
foreach($array as $k=>$a){
if($k==$lastkey){
/*do something*/
}
}
foreach ($array as $key => $value) {
$class = ( $key !== count( $array ) -1 ) ? " class='not-last'" : " class='last'";
echo "<div{$class}>";
echo "$value['the_title']";
echo "</div>";
}
Reference
If it is a single dimensional array you can do this to keep it short and sweet:
foreach($items as $idx => $item) {
if (!isset($items[$idx+1])) {
print "I am last";
}
}
Here's another way you could do it:
$arr = range(1, 10);
$end = end($arr);
reset($arr);
while( list($k, $v) = each($arr) )
{
if( $n == $end )
{
echo 'last!';
}
else
{
echo sprintf('%s ', $v);
}
}
If I understand you, then all you need is to reverse the array and get the last element by a pop command:
$rev_array = array_reverse($array);
echo array_pop($rev_array);
You could also try this to make your query... shown here with INSERT
<?php
$week=array('one'=>'monday','two'=>'tuesday','three'=>'wednesday','four'=>'thursday','five'=>'friday','six'=>'saturday','seven'=>'sunday');
$keys = array_keys($week);
$string = "INSERT INTO my_table ('";
$string .= implode("','", $keys);
$string .= "') VALUES ('";
$string .= implode("','", $week);
$string .= "');";
echo $string;
?>
For SQL query generating scripts, or anything that does a different action for the first or last elements, it is much faster (almost twice as fast) to avoid using unneccessary variable checks.
The current accepted solution uses a loop and a check within the loop that will be made every_single_iteration, the correct (fast) way to do this is the following :
$numItems = count($arr);
$i=0;
$firstitem=$arr[0];
$i++;
while($i<$numItems-1){
$some_item=$arr[$i];
$i++;
}
$last_item=$arr[$i];
$i++;
A little homemade benchmark showed the following:
test1: 100000 runs of model morg
time: 1869.3430423737 milliseconds
test2: 100000 runs of model if last
time: 3235.6359958649 milliseconds
Another way to go is to remember the previous loop cycle result and use that as the end result:
$result = $where = "";
foreach ($conditions as $col => $val) {
$result = $where .= $this->getAdapter()->quoteInto($col.' = ?', $val);
$where .= " AND ";
}
return $this->delete($result);

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