I have created an array list with the following code:
<?php
$ids = array();
if (mysql_num_rows($query1))
{
while ($result = mysql_fetch_assoc($query1))
{
$ids["{$result['user_id']}"] = $result;
}
}
mysql_free_result($query1);
?>
Now, i need to read two elements from the array. The first is the current and the second one is the next element of array. So, the simplified process is the following:
i=0: current_element (pos:0), next_element (pos:1)
i=1: current_element (pos:1), next_element (pos:2)
etc
To do this, i have already written the following code, but i cant get the next element for each loop!
Here is the code:
if (count($ids))
{
foreach ($ids AS $id => $data)
{
$userA=$data['user_id'];
$userB=next($data['user_id']);
}
}
The message i receive is: Warning: next() expects parameter 1 to be array, string given in array.php on line X
Does anyone can help? Maybe i try to do it wrongly.
The current, next, prev, end functions work with the array itself and place a position mark on the array. If you want to use the next function, perhaps this is the code:
if (is_array($ids))
{
while(next($ids) !== FALSE) // make sure you still got a next element
{
prev($ids); // move flag back because invoking 'next()' above moved the flag forward
$userA = current($ids); // store the current element
next($ids); // move flag to next element
$userB = current($ids); // store the current element
echo(' userA='.$userA['user_id']);
echo('; userB='.$userB['user_id']);
echo("<br/>");
}
}
You'll get this text on the screen:
userA=1; userB=2
userA=2; userB=3
userA=3; userB=4
userA=4; userB=5
userA=5; userB=6
userA=6; userB=7
userA=7; userB=8
You get the first item, then loop over the rest and at the end of each loop you move the current item as the next first item ... the code should explain it better:
if (false !== ($userA = current($ids))) {
while (false !== ($userB = next($ids))) {
// do stuff with $userA['user_id'] and $userB['user_id']
$userA = $userB;
}
}
Previous answer
You can chunk the arrays into pairs:
foreach (array_chunk($ids, 2) as $pair) {
$userA = $pair[0]['user_id']
$userB = $pair[1]['user_id']; // may not exist if $ids size is uneven
}
See also: array_chunk()
Related
So I have 2 files. In file 1 I have a table and there I randomly select some fields and store (store in session) them in an array of 2D arrays. When I click on the cell I send this data to my file 2 where I want to check if I clicked on a randomly selected array or not and if I did, I want to remove this 2D array from an main array.
But as soon as I click on one of the selected arrays, the array crashes.
File 1 PHP stuff immportant for this:
session_start();
$_SESSION['arrays'] = $stack ;
File 2 PHP:
session_start();
if (isset($_SESSION['arrays'])) {
$stack = $_SESSION['arrays'];
for ($i = 0; $i< count($stack);$i++){
if($cooridnates == $stack[$i]){
unset($stack[$i]);
array_values($stack);
$i--;
$Result = true;
break;
}
}
$_SESSION['arrays'] = $stack ;
I am suspecting the error might be in 2 things:
count($stack) used, but I don't believe this is the main reason.
The way I store session.
I have tried using manuals from W3Schools and official PHP website and also SOF, but with no use.
But still, I am not sure if the array_values() and unset() is working correctly since the thing chrashes and I can't test it correctly.
I would appreciate any tips.
You need to assign the result of array_values($stack); back to the $stack variable.
$stack = array_values($stack);
There's also no need to use $i-- when you do this, since you're breaking out of the loop after you find a match.
Instead of a loop, you can use array_search():
$pos = array_search($coordinates, $stack);
if ($pos !=== false) {
unset $stack[$pos];
$Result = true;
$stack = array_values($stack);
$_SESSION['arrays'] = $stack;
}
you can do this like that by using foreach loop:
session_start();
if (!empty($_SESSION['arrays'])) {
foreach( $_SESSION['arrays'] as $key => $val){
if($cooridnates == $val){
unset($_SESSION['arrays'][$key]); // if you want this removed value then assign it a variable before unsetting the array
$Result = true;
break;
}
}
}
This question has been asked a thousand times, but each question I find talks about associative arrays where one can delete (unset) an item by using they key as an identifier. But how do you do this if you have a simple array, and no key-value pairs?
Input code
$bananas = array('big_banana', 'small_banana', 'ripe_banana', 'yellow_banana', 'green_banana', 'brown_banana', 'peeled_banana');
foreach ($bananas as $banana) {
// do stuff
// remove current item
}
In Perl I would work with for and indices instead, but I am not sure that's the (safest?) way to go - even though from what I hear PHP is less strict in these things.
Note that after foreach has run, I expected var_dump($bananas) to return an empty array (or null, but preferably an empty array).
1st method (delete by value comparison):
$bananas = array('big_banana', 'small_banana', 'ripe_banana', 'yellow_banana', 'green_banana', 'brown_banana', 'peeled_banana');
foreach ($bananas as $key=>$banana) {
if($banana=='big_banana')
unset($bananas[$key]);
}
2nd method (delete by key):
$bananas = array('big_banana', 'small_banana', 'ripe_banana', 'yellow_banana', 'green_banana', 'brown_banana', 'peeled_banana');
unset($bananas[0]); //removes the first value
unset($bananas[count($bananas)-1]); //removes the last value
//unset($bananas[n-1]); removes the nth value
Finally if you want to reset the keys after deletion process:
$bananas = array_map('array_values', $bananas);
If you want to empty the array completely:
unset($bananas);
$bananas= array();
it still has the indexes
foreach ($bananas as $key => $banana) {
// do stuff
unset($bananas[$key]);
}
for($i=0; $i<count($bananas); $i++)
{
//doStuff
unset($bananas[$i]);
}
This will delete every element after its use so you will eventually end up with an empty array.
If for some reason you need to reindex after deleting you can use array_values
How about a while loop with array_shift?
while (($item = array_shift($bananas)) !== null)
{
//
}
Your Note: Note that after foreach has run, I expected var_dump($bananas) to return an empty array (or null, but preferably
an empty array).
Simply use unset.
foreach ($bananas as $banana) {
// do stuff
// remove current item
unset($bananas[$key]);
}
print_r($bananas);
Result
Array
(
)
This question is old but I will post my idea using array_slice for new visitors.
while(!empty($bananas)) {
// ... do something with $bananas[0] like
echo $bananas[0].'<br>';
$bananas = array_slice($bananas, 1);
}
I am trying to fill a array with a csv so each field is separate part of the array, when i have filled the array and echo it out it quite literally says array for every enter.
I have a feeling that once i sort the csvfull array that the sku might need to be in loop inside the main processing loop to.
$ocuk = fopen("ocuk.csv", "r");
while (($result = fgetcsv($ocuk)) !== false)
{
$csvfull[] = $result;
}
print_r ($csvfull[0][1]);
$sku="$csvfull[1]";
while (($csv = fgetcsv($ocuk)) !== FALSE)
{
if (false === empty(array_intersect($sku, $csv)))
{
code to display the results from csv that match the $sku variable
}
}
What i need it to do is csvfull array to fill with the contents of the csv such i can then call it into the variable sku to do comparison in next part of the code.
EDIT example of what i mean
csv example
data,data2,data3,data4 etc
data10,data20,data30,data40 etc
the array would then be like this
$csvfull=array() would contain the below
array("data","data2","data3","data4");
array("data10","data20","data30","data40");
then when i call csvfull[1] it display data2 then would go onto data 20 etc
$csvfull is a 2-dimensional array. The first dimension is the rows of the CSV, the second dimension is the columns. So $csvfull[1] is an array containing all the values from the second line of the file. To get the SKU, you need to drill down to the appropriate column, e.g.
foreach ($csvfull as $row) {
$sku = $row[1];
// Do something with $sku
}
If you want to get an array of all the SKUs, you can do:
$sku = array();
foreach ($csvfull as $row) {
$sku[] = $row[1];
}
try like this:
<?php
$ocuk = fopen('clientes.csv','r');
$i=0;
while(!feof($ocuk)){
$values = fgetcsv($ocuk);
if(empty($values[1] )){ // any index which is not empty to make sure that you are reading valid row.
continue;}
$csvfull[$i] = $values;
$i++;
}
print_r($csvfull);
.
fclose($ocuk);
I would like to pass in an array that contains a list of directories to scan. I want to iterate over each directory and push its content into another array that I will print out, but for some reason my code is not working. The directories exist and the path is correct. I think it has something to do with how I'm using foreach.
These are the errors I'm getting:
Notice: Undefined index: C:\Users\john\Desktop\files\images\ in
C:\xampp\htdocs\test.php on line 6
Warning: scandir(): Directory name cannot be empty in
C:\xampp\htdocs\test.php on line 6
This is the code:
function test($dir = []) {
foreach($dir as $bar) {
$list = [];
array_push($list, scandir($dir[$bar]));
}
print_r($list);
}
test(["C:\Users\john\Desktop\files\images\\", "C:\Users\john\Desktop\files\images\autumn\\"]);
If anyone can think of a simpler way to do this, please don't hesitate to tell me.
You're on the right track. There are a few changes you need to make though.
function test($dir = []) {
$list = [];
foreach($dir as $bar) {
$list[] = scandir($bar);
}
print_r($list);
}
As noted by #BrianPoole you need to move the $list out of the foreach loop. By having it in the loop, the array is reset with each iteration, resulting in the final array having one element.
In addition, the foreach loop as explained above by #TimCooper does not operate the same as in JavaScript. If you really want to access the keys, you can use the following syntax:
foreach($dir as $key => $bar)
You would then use either $dir[$key] or $bar to access the directory value.
Finally, array_push is an additional function call that in your case is not needed. By simply adding [] PHP will push the new value onto the end of the array.
function test($dir) {
// DEFINE LIST OUT SIDE OF LOOP
$list = array();
// Run checks
if(count($dir) > 0) {
// Loop Through Directory
foreach($dir as $directory) {
// Push into list
array_push($list, array("scanned"=>$directory, "contents" => scandir($directory)));
}
}else {
// If no directories are passed return array with error
$list = array(
"error" => 1,
"message" => "No directories where passed into test()",
);
}
print_r($list);
}
This is how I would do it. It provides a couple checks and sets up the data so you can se it a bit more clear.
I am new in PHP and I have little problem. I have code like this:
$file = $_FILES['sel_file']['name'];
$chk_ext = explode(".",$file);
if(strtolower($chk_ext[1]) == "txt")
{
$filename = $_FILES['sel_file']['tmp_name'];
$handle = fopen($filename, "r");
while (($data = fgetcsv($handle, 1000, ",")) !== FALSE)
{
$array = array( $data[0]);
foreach( $array as $value )
{
$number=$value;
}
$obj=new Sender("$number");
}
header("location:bulk.php?msg=send");
}
else
{
header("location:bulk.php?invalid=file");
exit();
}
$obj->Submit ();
Problem is that only last value comes out from text file in $obj=new Sender("$number");, please help me out.
fgetcsv() already return an array so: $array = array( $data[0]); just means that you only retrieve the first element of the array of fields which is $data.
In the foreach loop you should just replace the $array variable with $data.
The loop woould then look like this:
foreach( $data as $value )
{
$number=$value;
}
$obj=new Sender("$number");
means that for every element in $data, you hold it inside $number, loops again and put it again in $number overwriting it.
After the foreach loop the value of $number would be the last field of the row.
You should just put the line $obj=new Sender("$number"); inside the loop, so that every element of every row would be put in Sender.
No surprise. You loop over all the values, continually overwriting $number with the most recently retrieved value. When the loop exits, you end up with only the last one.
Probably you want something more like:
foreach($array as $value) {
$obj = new Sender($value);
}
your code also makes very little sense. You take an uploaded file, presumably CSV, read a line from it, extract the FIRSt value from that line. force the value into an array, then read back that ONE value in the array (the ONLY value in the array), and do something with it.
Even if your foreach wasn't overwriting the value, you still only have one single value to loop on anyways.
You are overwriting the contents of number each iteration. You can instead make number an array which stores each value at incrementing elements.
foreach( $array as $value )
{
$number[]=$value;
}
$obj=new Sender($number);
That's because you assign a new value to $number in each iteration. Either you need to append to that variable ($number .= $value) or you need to add it to an array ($number[] = $value).