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I have an array that looks like this...
Array
(
[0] => red
[1] => red
[2] => red
)
I am trying to check if red is the only thing in the array, I would want it to fail if the array looked like this...
Array
(
[0] => red
[1] => yellow
[2] => red
)
Using array_unique() you can just count the number of occurances returned. If its > 1 you have not got all red
<?php
$array = ['red','red','red'];
if ( count(array_unique($array)) == 1 && array_unique($array)[0] == 'red' ) {
echo 'all red';
} else {
echo 'error';
}
Use combination of count() and array_filter() to find count of unwanted item in array.
$invalidItems = count(array_filter($arr, function($item){
return $item != 'red';
}));
if ($invalidItems)
echo 'invalid';
else
echo 'valid';
Check result in demo
You could just use array_unique() to get it to remove duplicates and then count the size of the remaining list, you can also then check that the 1 value is whatever value your expecting...
$unique = array_unique($a);
if ( count($unique) == 1 && $unique[0] == 'value' ) {
}
You can do it like this:
$array = [
'foo',
'foo',
'foo'
];
$values = array_count_values($array);
$count = count($array);
if (!empty($values['foo']) && $count === $values['foo']) {
echo 'all array values match foo';
} else {
echo 'foo not found in array';
}
here we count values in the array vs the overall count of the array
Edit: The only problem is, you have to know the value you're comparing against to get the result
Edit 2: Addressing issue raised by MickMackusa:
and the other problem is, if the value that you are looking for doesn't exist at all in the input array, then it won't exist as a key in the $values array and thus your code will generate a Notice. ...not good.
You don't need more than one function call to check for non-red values exist. The following checks if there are any non-red elements.
Codes (Demo)
$array = ['red','red','red'];
var_export(!array_diff($array, ['red'])); // true
echo "\n";
var_export(!array_filter($array, function($v){return $v !== 'red';})); // true
$array = ['red','yellow','red'];
var_export(!array_diff($array, ['red'])); // false
echo "\n";
var_export(!array_filter($array, function($v){return $v !== 'red';})); // false
I think array_filter() is a more "direct" technique, but array_diff() doesn't need a custom function so it is arguably easier to read.
If your coding logic must require the existence of red as well as disqualify arrays that contain a non-red element, then just add a condition that checks if the array has any elements. (more precise demo)
And for best performance, use a loop with a break -- this way you don't have to iterate the entire array unless absolutely necessary. Early breaks are a good thing. Demo
$array = ['red','yellow','red'];
$result = true;
foreach ($array as $value) {
if ($value != 'red') {
$result = false;
break;
}
}
Check if red is there, then remove duplicate values and check that there is only one:
if(in_array('red', $array) && (count(array_unique($array)) == 1)) {
// yes
}
Old school foreach (all) red or dead:
<?php
$things = ['red', 'white', 'blue'];
foreach($things as $colour)
if ($colour !== 'red')
throw new Exception('dead');
So my question might not be the best, so sorry for that.
I have an array with strings and want to write a text with the help of another array using it as the order/key. This is the Input:
$words =["I","am","cool"];
$order =["2","0","1","0","1","2"];
//var_export($words);
// array (
// 0 => 'I',
// 1 => 'am',
// 2 => 'cool',
// )
I want to use $order as some sort of key to rearrange $words so I can get this Output:
"Cool I am I am cool"
Help is much appreciated, thank you :)
Use the values of $order as the keys for $words.
$words =["I","am","cool"];
$order =["2","0","1","0","1","2"];
$output = '';
foreach($order as $key) {
$output .= $words[$key] . ' ';
}
echo ucfirst(trim($output));
Demo: https://eval.in/780785
The empty($real_key) is to check if it is the first iteration. Also could be == 0.
I would recommend the use of array_map and join
There is no need for
side-effecting manual iteration using foreach
if statements or ternary (?:) expressions
variable reassignment
string concatenation using .
checking array lengths
Here we go
function map_indexes_to_words ($indexes, $words) {
$lookup = function ($i) use ($words) {
return $words[(int) $i];
};
return join(' ', array_map($lookup, $indexes));
}
$words = ["I","am","cool"];
$order = ["2","0","1","0","1","2"];
echo map_indexes_to_words($order, $words);
// 'cool I am I am cool'
Start with an empty array.
Then loop through the order array and add the word array part to the new string.
$my_string= array();
foreach ( $order as $index ) {
$index = int($index);
$my_string[] = ( isset($words[ $index]) ) ? $words[ $index ] : '' );
}
$my_string = implode(' ', $my_string);
echo my_string;
Iterate over order and use it's values as keys to words; Convert the following code to php it should be pretty simple...
foreach (string orderIndexString in order) {
int orderIndexInt = System.Convert.ToInt16(orderIndexString); // convert string to int
if(orderIndexInt < 0 || orderIndexInt >= words.Length)
continue;
print (words[orderIndexInt]); // either print or add it to another string
}
I have a page with a form where I post all my checkboxes into one array in my database.
The values in my database looks like this: "0,12,0,15,58,0,16".
Now I'm listing these numbers and everything works fine, but I don't want the zero values to be listed on my page, how am I able to search through the array and NOT list the zero values ?
I'm exploding the array and using a for each loop to display the values at the moment.
The proper thing to do is to insert a WHERE statement into your database query:
SELECT * FROM table WHERE value != 0
However, if you are limited to PHP just use the below code :)
foreach($values AS $key => $value) {
//Skip the value if it is 0
if($value == 0) {
continue;
}
//do something with the other values
}
In order to clean an array of elements, you can use the array_filter method.
In order to clean up of zeros, you should do the following:
function is_non_zero($value)
{
return $value != 0;
}
$filtered_data = array_filter($data, 'is_non_zero');
This way if you need to iterate multiple times the array, the zeros will already be deleted from them.
you can use array_filter for this. You can also specify a callback function in this function if you want to remove items on custom criteria.
Maybe try:
$out = array_filter(explode(',', $string), function ($v) { return ($v != 0); });
There are a LOT of ways to do this, as is obvious from the answers above.
While this is not the best method, the logic of this might be easier for phpnewbies to understand than some of the above methods. This method could also be used if you need to keep your original values for use in a later process.
$nums = '0,12,0,15,58,0,16';
$list = explode(',',$nums);
$newList = array();
foreach ($list as $key => $value) {
//
// if value does not equal zero
//
if ( $value != '0' ) {
//
// add to newList array
//
$newList[] = $value;
}
}
echo '<pre>';
print_r( $newList );
echo '</pre>';
However, my vote for the best answer goes to #Lumbendil above.
$String = '0,12,0,15,58,0,16';
$String = str_replace('0', '',$String); // Remove 0 values
$Array = explode(',', $String);
foreach ($Array AS $Values) {
echo $Values."<br>";
}
Explained:
You have your checkbox, lets say the values have been converted into a string. using str_replace we have removed all 0 values from your string. We have then created an array by using explode, and using the foreach loop. We are echoing out all the values of th array minux the 0 values.
Oneliner:
$string = '0,12,0,15,58,0,16';
echo preg_replace(array('/^0,|,0,|,0$/', '/^,|,$/'), array(',', ''), $string); // output 12,15,58,16
Edit: The aim of my method is to delete a value from a string in a database.
I cant seem to find the answer for this one anywhere. Can you concatenate inside a str_replace like this:
str_replace($pid . ",","",$boom);
$pid is a page id, eg 40
$boom is an exploded array
If i have a string: 40,56,12 i want to make it 56,12 however without the concatenator in it will produce:
,56,12
When I have the concat in the str_replace it doesnt do a thing. Is this possible?
Answering your question: yes you can. That code works as you would expect it to.
But this approach is wrong. It will not work for $pid = 12; (last element, without trailing coma) and will incorrectly replace 40, in $boom = '140,20,12';
You should keep it in array, search for unwanted value, if found unset it from the array and then implode with coma.
$boom = array_filter($boom);
$key = array_search($pid, $boom);
if($key !== false){
unset($boom[$key]);
}
$boom = implode(',',$boom);
[+] Your code does not work because $boom is an array, and str_replace operates on string.
As $boom is an array, you don't need to use array on your case.
Change this
$boom = explode(",",$ticket_array);
$boom = str_replace($pid . ",","",$boom);
$together = implode(",",$boom);
to
$together = str_replace($pid . ",","",$ticket_array);
Update: If you want still want to use array
$boom = explode(",",$ticket_array);
unset($boom[array_search($pid, $boom)]);
$together = implode(",",$boom);
After you have edited it becomes clear that you want to remove the value of $pid from the array $boom which contains one number as a value. You can use array_search to find if it is in at if in with which key. You can then unset the element from $boom:
$pid = '40';
$boom = explode(',', '40,56,12');
$r = array_search($pid, $boom, FALSE);
if ($r !== FALSE) {
unset($boom[$r]);
}
Old question:
Can you concatenate inside a str_replace like this: ... ?
Yes you can, see the example:
$pid = '40';
$boom = array('40,56,12');
print_r(str_replace($pid . ",", "", $boom));
Result:
Array
(
[0] => 56,12
)
Which is pretty much like you did so you might be looking for the problem at the wrong place. You can use any string expression for the parameter.
It might be easier for you if you're unsure to create a variable first:
$pid = '40';
$boom = array('40,56,12');
$search = sprintf("%d,", $pid);
print_r(str_replace($search, "", $boom));
You should store your "ticket array" in a separate table.
And use regular SQL queries (UPDATE, DELETE) to manipulate it.
A relational word in the name of your database is for the reason. And you are abusing this smart software with such a barbaric approach.
You could use str_split, it converts a string to an array, then with a foreach loop echo all the values except the first one.
$numbers_string="40,56,12";
$numbers_array = str_split($numbers_string);
//then, when you have the array of numbers, you could echo every number except the first separating them with a comma
foreach ($numbers_array as $key => $value) {
if ($key > 0) {
echo $value . ", ";
}
}
If you want is to skip a value not by it's position in the array, but for it's value then you could do this instead:
$unwanted_value="40";
foreach ($numbers_array as $key => $value) {
if ($value != $unwanted_value) {
echo $value . ", ";
}
else {
unset($numbers_array[$key]);
$numbers_array = array_values($numbers_array);
var_dump($numbers_array);
}
}
I want to replace all array values with 0 except work and home.
Input:
$array = ['work', 'homework', 'home', 'sky', 'door']
My coding attempt:
$a = str_replace("work", "0", $array);
Expected output:
['work', 0, 'home', 0, 0]
Also my input data is coming from a user submission and the amount of array elements may be very large.
A bit more elegant and shorter solution.
$aArray = array('work','home','sky','door');
foreach($aArray as &$sValue)
{
if ( $sValue!='work' && $sValue!='home' ) $sValue=0;
}
The & operator is a pointer to the particular original string in the array. (instead of a copy of that string)
You can that way assign a new value to the string in the array. The only thing you may not do is anything that may disturb the order in the array, like unset() or key manipulation.
The resulting array of the example above will be
$aArray = array('work','home', 0, 0)
A loop will perform a series of actions many times. So, for each element in your array, you would check if it is equal to the one you want to change and if it is, change it. Also be sure to put quote marks around your strings
//Setup the array of string
$asting = array('work','home','sky','door')
/**
Loop over the array of strings with a counter $i,
Continue doing this until it hits the last element in the array
which will be at count($asting)
*/
for($i = 0; $i < count($asting);$i++){
//Check if the value at the 'ith' element in the array is the one you want to change
//if it is, set the ith element to 0
if ($asting[$i] == 'work' || $asting[$i] == 'home')
$asting[$i] = 0;
}
Here is some suggested reading:
http://www.php.net/manual/en/language.types.array.php
http://www.php.net/manual/en/language.control-structures.php
But if you are struggling on stuff such as looping, you may want to read some introductory programming material. Which should help you really understand what's going on.
A bit other and much quicker way, but true, need a loop:
//Setup the array of string
$asting = array('bar', 'market', 'work', 'home', 'sky', 'door');
//Setup the array of replacings
$replace = array('home', 'work');
//Loop them through str_replace() replacing with 0 or any other value...
foreach ($replace as $val) $asting = str_replace($val, 0, $asting);
//See what results brings:
print_r ($asting);
Will output:
Array
(
[0] => bar
[1] => market
[2] => 0
[3] => 0
[4] => sky
[5] => door
)
An alternative using array_map:
$original = array('work','home','sky','door');
$mapped = array_map(function($i){
$exclude = array('work','home');
return in_array($i, $exclude) ? 0 : $i;
}, $original);
you may try array_walk function:
function zeros(&$value)
{
if ($value != 'home' && $value != 'work'){$value = 0;}
}
$asting = array('work','home','sky','door','march');
array_walk($asting, 'zeros');
print_r($asting);
You can also give array as a parameter 1 and 2 on str_replace...
Just a small point to the for loop. Many dont realize the second comparing task is done every new iteration. So if it was a case of big array or calculation you could optimize loop a bit by doing:
for ($i = 0, $c = count($asting); $i < $c; $i++) {...}
You may also want to see http://php.net/manual/en/function.array-replace.php for original problem unless the code really is final :)
Try This
$your_array = array('work','home','sky','door');
$rep = array('home', 'work');
foreach($rep as $key=>$val){
$key = array_search($val, $your_array);
$your_array[$key] = 0;
}
print_r($your_array);
There are a few techniques on this page that make zero iterated function calls -- which is good performance-wise. For best maintainability, I recommend separating your list of targeted string as a lookup array. By modifying the original array values by reference, you can swiftly replace whole strings and null coalesce non-targeted values to 0.
Code: (Demo)
$array = ['work', 'homework', 'home', 'sky', 'door'];
$keep = ['work', 'home'];
$lookup = array_combine($keep, $keep);
foreach ($array as &$v) {
$v = $lookup[$v] ?? 0;
}
var_export($array);
Output:
array (
0 => 'work',
1 => 0,
2 => 'home',
3 => 0,
4 => 0,
)
You can very easily, cleanly extend your list of targeted strings by merely extending $keep.
If you don't want a classic loop, you can use the same technique without modifying the original array. (Demo)
var_export(
array_map(fn($v) => $lookup[$v] ?? 0, $array)
);
this my final code
//Setup the array of string
$asting = array('work','home','sky','door','march');
/**
Loop over the array of strings with a counter $i,
Continue doing this until it hits the last element in the array
which will be at count($asting)
*/
for($i = 0; $i < count($asting); $i++) {
//Check if the value at the 'ith' element in the array is the one you want to change
//if it is, set the ith element to 0
if ($asting[$i] == 'work') {
$asting[$i] = 20;
} elseif($asting[$i] == 'home'){
$asting[$i] = 30;
}else{
$asting[$i] = 0;
}
echo $asting[$i]."<br><br>";
$total += $asting[$i];
}
echo $total;