I have an array. Say example
array('x'=>1);
this is having only one element. This array can change. Key change but only one element will be there. e.g. next time the array can be like --
array('y'=>1);
Now the problem is - I don't know the key name, I need the key name and the value as well.
But as it is having only one element I don't want to run a foreach.
Is it possible ?
For that you can use key function
Try this here snippet here
$array=array('x'=>1);
echo key($array);//x
You should try with: array_search()
Hope this will help you.
$key = array_keys($array)[0];
$value = $array[$key];
Related
Hello im trying to do this but print or vap_dump show nothing as value. it works with string but not with integer
$a=array("a"=>"red","b"=>"green");
array_push($a['new'],1);
print_r($a);
Help, thanks
Check docs for array_push.
https://www.php.net/manual/en/function.array-push.php
First argument is the array you want to push to.
In your example you are trying to add an element to $a['new'], but $a['new'] is not an array.
So do this instead.
$a=array("a"=>"red","b"=>"green");
array_push($a,1);
print_r($a);
Edit:
As ADyson mentioned, if your intent is to add a value with a specific key, you would simply do:
$a['new'] = 1;
Which one would you use?
Basically I only want to get the 1st element from a array, that's it.
Well, they do different things.
array_shift($arr) takes the first element out of the array, and gives it to you.
$arr[0] just gives it to you... if the array has numeric keys.
An alternative that works for associative arrays too is reset($arr). This does move the array's internal pointer, but unless you're using those functions this is unlikely to affect you.
array_shift will actually remove the specified value from the array. Do not use it unless you really want to reduce the array!
See here: http://php.net/manual/en/function.array-shift.php
You would use $arr[ 0 ]; array_shift removes the first element from the array.
EDIT
This answer is actually somewhere between incomplete and plain out wrong but, because the comments of the two jon's I think that it should actually stay up so that others can see that discourse.
The right answer:
reset is the method to return the first defined index of the array. Even in non-associative arrays, this may not be the 0 index.
array_shift will remove and return the value which is found at reset
The OP made the assumption that $arr[0] is the first index is not accurate in that particular context.
$arr[0] only works if the array as numerical keys.
array_shift removes the element from the array and it modifies the array itself.
If you are not sure what the first key is , and you do not want to remove it from the array, you could use:
<?php
foreach($arr $k=>$v){
$value = $v;
break;
}
or even better:
<?php
reset($arr);
$value = current($arr);
If you have an associative Array you can also use reset($arr): It returns the first Element (doesn't remove), and sets the array pointer to this element.
But the fastest way is $arr[0].
Do you want to modify the arr array also? array_shift removes the first element of the array and returns it, thus the array has changed. $arr[0] merely gives you the first element.
I would use $arr[0] unless I explicitly wanted to modify the array. You may add code later to use the arr array and forget that it was modified.
given what you need, $arr[0] is preferrable, because it's faster. array_shift is used in other situations.
arrshift is more reliable and will always return the first element in the array, but this also modifies the array by removing that element.
arr[0] will fail if your array doesn't start at the 0 index, but leaves the array itself alone.
A more convoluted but reliable method is:
$keys = array_keys($arr);
$first = $arr[$keys[0]];
with array_shif you have two operations:
retrive the firs element
shift the array
if you access by index, actually you have only one operation.
If you want the first element of an array, use $arr[0] form. Advantages - Simplicity, Readability and Maintainability. Keep things straight forward.
Edit: Use index 0 only if you know that the array has default keys starting from 0.
If you don't want to change the array in question, use $arr[0] (which merely gets the first element), otherwise if you want to remove the first element of $arr from $arr, use array_shift($arr).
For example:
$arr=array(3,-6,2);
$foo=$arr[0]; //$foo==3 and $arr==array(3,-6,2).
$bar=array_shift($arr); //$bar==3 and $arr==array(-6,2).
ETA: As others have pointed out, be sure that your array isn't an associative array (ie the keys are 0,1,...,(sizeof($arr)-1)), otherwise this probably won't work.
Which one would you use?
Basically I only want to get the 1st element from a array, that's it.
Well, they do different things.
array_shift($arr) takes the first element out of the array, and gives it to you.
$arr[0] just gives it to you... if the array has numeric keys.
An alternative that works for associative arrays too is reset($arr). This does move the array's internal pointer, but unless you're using those functions this is unlikely to affect you.
array_shift will actually remove the specified value from the array. Do not use it unless you really want to reduce the array!
See here: http://php.net/manual/en/function.array-shift.php
You would use $arr[ 0 ]; array_shift removes the first element from the array.
EDIT
This answer is actually somewhere between incomplete and plain out wrong but, because the comments of the two jon's I think that it should actually stay up so that others can see that discourse.
The right answer:
reset is the method to return the first defined index of the array. Even in non-associative arrays, this may not be the 0 index.
array_shift will remove and return the value which is found at reset
The OP made the assumption that $arr[0] is the first index is not accurate in that particular context.
$arr[0] only works if the array as numerical keys.
array_shift removes the element from the array and it modifies the array itself.
If you are not sure what the first key is , and you do not want to remove it from the array, you could use:
<?php
foreach($arr $k=>$v){
$value = $v;
break;
}
or even better:
<?php
reset($arr);
$value = current($arr);
If you have an associative Array you can also use reset($arr): It returns the first Element (doesn't remove), and sets the array pointer to this element.
But the fastest way is $arr[0].
Do you want to modify the arr array also? array_shift removes the first element of the array and returns it, thus the array has changed. $arr[0] merely gives you the first element.
I would use $arr[0] unless I explicitly wanted to modify the array. You may add code later to use the arr array and forget that it was modified.
given what you need, $arr[0] is preferrable, because it's faster. array_shift is used in other situations.
arrshift is more reliable and will always return the first element in the array, but this also modifies the array by removing that element.
arr[0] will fail if your array doesn't start at the 0 index, but leaves the array itself alone.
A more convoluted but reliable method is:
$keys = array_keys($arr);
$first = $arr[$keys[0]];
with array_shif you have two operations:
retrive the firs element
shift the array
if you access by index, actually you have only one operation.
If you want the first element of an array, use $arr[0] form. Advantages - Simplicity, Readability and Maintainability. Keep things straight forward.
Edit: Use index 0 only if you know that the array has default keys starting from 0.
If you don't want to change the array in question, use $arr[0] (which merely gets the first element), otherwise if you want to remove the first element of $arr from $arr, use array_shift($arr).
For example:
$arr=array(3,-6,2);
$foo=$arr[0]; //$foo==3 and $arr==array(3,-6,2).
$bar=array_shift($arr); //$bar==3 and $arr==array(-6,2).
ETA: As others have pointed out, be sure that your array isn't an associative array (ie the keys are 0,1,...,(sizeof($arr)-1)), otherwise this probably won't work.
if (in_array($form['#submit'], 'search_box_form_submit')) {
$key = array_search('search_box_form_submit', $form['#submit']);
unset($form['#submit'][$key]);
}
array_unshift($form['#submit'], 'mymodule_search_box_submit');
What does the code do? I don't follow it well; I expect someone can explain it to me, line by line.
If the submitted form contains a variable named "search_box_form_submit", delete it, and then add a new variable called "mymodule_search_box_submit".
Perhaps somebody wanted to override the drupal search function and didn't want the default processor to fire at all. Thanks kiamlaluno in the comments.
if (in_array($form['#submit'], 'search_box_form_submit')) {
If the value 'search_box_form_submit' is present in the array $form['#submit']
$key = array_search('search_box_form_submit', $form['#submit']);
Then set the variable $key to the array key for the value 'search_box_form_submit' in the array $form['#submit']
unset($form['#submit'][$key]);
Then unset (delete) that array element
array_unshift($form['#submit'], 'mymodule_search_box_submit');
Put a new element at the beginning of the array $form['#submit'] with the value 'mymodule_search_box_submit'
is the text "search_box_form_submit" in the array $form['#submit']
if so find the key for search_box_form_submit
then remove from array
put the value mymodule_search_box_submit in the front of the array $form['#submit']
i recommend reading the manual page for the functions used.
When I send over post data I do a print_r($_POST); and I get something like this...
Array ( [gp1] => 9 )
Is there a way to get the "gp1", the name sent over as a value? I tried doing.
echo key($_POST["gp1"]);
But no luck there, I figured it would echo gp1. Is there a way to do this?
you need
print_r(array_keys($_POST));
check this for more details http://php.net/manual/en/function.array-keys.php
You could use foreach to see each key-value pair, or use array_keys to get a list of all keys.
foreach ($_POST as $key => $value) {
// Do whatever
}
Well, if you can write $_POST["gp1"] you already have the key anyway ;)
key() works differently, it takes an array as argument:
The key() function simply returns the key of the array element that's currently being pointed to by the internal pointer. It does not move the pointer in any way. If the internal pointer points beyond the end of the elements list or the array is empty, key() returns NULL.
So if you have not done anything with the array (no traversing), key($_POST) would give you the key of the first element of the array.
Maybe you want a foreach loop?
foreach($_POST as $key => $value) {
}
There are other methods to retrieve keys as to well. It depends on what you want to do.