I have a cookie which I'm trying to split. The cookie is in this format:
key = val1,val2,val3 (where each value is separated by commas)
is there a way for me to split this in a loop so that I can directly access val3?
I've tried using the explode() function with no success.
for ($i = 0; $i < count($_COOKIE); $i++)
{
$ind = key($_COOKIE);
$data = $_COOKIE[$ind];
//I try and slit the cookie here
$cookie_temp = explode(",",$_COOKIE[$ind]);
//Here is where I wanted to display Val3 from the cookie
print $cookie_temp[2];
next($_COOKIE);
}
my code works fine but I then end up with all my Val3 in a large array. For example, my val3's are numbers and they get put in an array. Can I split this even further?
First of all, I'm hoping you know the name of the cookie you're trying to get the value of. Let's call it mycookie in the rest of my answer.
Second, just scrap the whole loop thing and just access $_COOKIE['mycookie'] directly.
Then, you can now call explode(",",$_COOKIE['mycookie']) to get the separate values.
Next, just get index 2 with [2] as you are in your current code.
As a shortcut, if the second one is the only one you need:
list(,,$val) = explode(",",$_COOKIE['mycookie']);
Assuming you are looping because you have multiple comma-separated cookie key/value groups, use a foreach() instead and with list() you can retrieve the third value with a direct assignment.
foreach ($_COOKIE as $key=>$value) {
list($v1, $v2, $v3) = explode("," $value);
echo $v3;
}
If you have only one cookie value to access, there is no need for the loop, and you can directly call explode(",", $_COOKIE['key'])
PHP 5.4 allows array dereferencing, whereby you can directly access the array element off of the explode() call, but this won't work in earlier PHP versions.
echo explode(",", $_COOKIE['key'])[2];
Related
I am attempting to use a for loop or for each loop to push the values from a get query to another variable. May I have some help with this approach?
Ok here is where I am:
for ($i = 0 ; i < $_GET['delete']; i++) {
$_jid [] = $_GET['delete'];
}
You don't actually need a loop here. If $_jid already is an array containing some values, consider just merging it with $_GET['delete'].
if (is_array($_jid)) {
$_jid = array_merge($_jid, $_GET['delete']);
}
If $_jid is not an array and doesn't exist except as a container for $_GET['delete'] you do can just assign the array. There is no need to loop at all.
$_jid = $_GET['delete'];
Of course in that case, you don't even need to copy it. You can just use $_GET['delete'] directly, in any context you planned to read from $_jid.
Update:
If the contents of $_GET['delete'] are originally 923,936, that is not an array to begin with, but rather a string. If you want an array out of it, you need to explode() it on assignment:
$_jid = explode(',', $_GET['delete']);
But if you intend to implode() it in the end anyway, there's obviously no need to do that. You already have exactly the comma-delimited string you want.
As you can see if you do a var_dump($_GET), the variable $_GET is a hashmap.
You can easily use a foreach loop to look through every member of it :
foreach($_GET as $get) // $get will successively take the values of $_GET
{
echo $get."<br />\n"; // We print these values
}
The code above will print the value of the $_GET members (you can try it with a blank page and dull $_GET values, as "http://yoursite.usa/?get1=stuff&get2=morestuff")
Instead of a echo, you can put the $_GET values into an array (or other variables) :
$array = array(); // Creating an empty array
$i = 0; // Counter
foreach($_GET as $get)
{
$array[$i] = $get; // Each $_GET value is store in a $array slot
$i++;
}
In PHP, foreach is quite useful and very easy to use.
However, you can't use a for for $_GET because it's a hashmap, not an array (in fact, you can, but it's much more complicated).
Hope I helped
how to slice an array to pass it to a function. I cannot use unset because I need that array further. I know I can copy whole array to variable, however it's quite big and don't thing it's efficient. My code:
$list = array(0=>2123, 2=>1231, 7=>123123,...);
unset($list[0]); //I can't do this because I still need whole $list
$seats = $allocatingClass->allocateSeats($seatsNumber, $list); //here I need to slice $key from $list and pass $list without reiterating
If you need to keep index 0, store it, rather than storing the entire array elsewhere:
$tmp = $list[0];
Then splice the array:
$list = array_splice($list,1,count($list));
Then pass it to your function:
$seats = $allocatingClass->allocateSeats($seatsNumber, $list);
Then, when you need it, put back the value to the array:
$list[] = $tmp;
Edit: if you actually need to put it exactly at index 0, then you may want to unset the index 0 of the array instead of splicing it. If you can, however, push it at the end of the array just follow what is written above.
To clearify, if you need to LATER push back the element to index 0, do
unset($list[0]);
instead of the splice...
And to put back the element, do:
$list[0] = $tmp;
However you do it, a copy will be made when passing the array (unless you pass it by reference).
either use splice. or create a copy and shift one value.
after sending the copy variable, you can unset it so it wont keeptaking its space.
Edit :
The above solution is also viable. Though I suggest you use:
$tmp = array_shift($arr);
doStuf($arr);
array_unshift($arr, $tmp);
In the PHP manual, (array_push) says..
If you use array_push() to add one element to the array it's better to
use $array[] = because in that way there is no overhead of calling a
function.
For example :
$arr = array();
array_push($arr, "stackoverflow");
print_r($arr);
vs
$arr[] = "stackoverflow";
print_r($arr);
I don't understand why there is a big difference.
When you call a function in PHP (such as array_push()), there are overheads to the call, as PHP has to look up the function reference, find its position in memory and execute whatever code it defines.
Using $arr[] = 'some value'; does not require a function call, and implements the addition straight into the data structure. Thus, when adding a lot of data it is a lot quicker and resource-efficient to use $arr[].
You can add more than 1 element in one shot to array using array_push,
e.g. array_push($array_name, $element1, $element2,...)
Where $element1, $element2,... are elements to be added to array.
But if you want to add only one element at one time, then other method (i.e. using $array_name[]) should be preferred.
The difference is in the line below to "because in that way there is no overhead of calling a function."
array_push() will raise a warning if the first argument is not
an array. This differs from the $var[] behaviour where a new array is
created.
You should always use $array[] if possible because as the box states there is no overhead for the function call. Thus it is a bit faster than the function call.
array_push — Push one or more elements onto the end of array
Take note of the words "one or more elements onto the end"
to do that using $arr[] you would have to get the max size of the array
explain:
1.the first one declare the variable in array.
2.the second array_push method is used to push the string in the array variable.
3.finally it will print the result.
4.the second method is directly store the string in the array.
5.the data is printed in the array values in using print_r method.
this two are same
both are the same, but array_push makes a loop in it's parameter which is an array and perform $array[]=$element
Thought I'd add to the discussion since I believe there exists a crucial difference between the two when working with indexed arrays that people should be aware of.
Say you are dynamically creating a multi-dimensional associative array by looping through some data sets.
$foo = []
foreach ($fooData as $fooKey => $fooValue) {
foreach ($fooValue ?? [] as $barKey => $barValue) {
// Approach 1: results in Error 500
array_push($foo[$fooKey], $barKey); // Error 500: Argument #1 ($array) must be of type array
// NOTE: ($foo[$fooKey] ?? []) argument won't work since only variables can be passed by reference
// Approach 2: fix problem by instantiating array beforehand if it didn't exist
$foo[$fooKey] ??= [];
array_push($foo[$fooKey], $barKey);
// Approach 3: One liner approach
$foo[$fooKey][] = $barKey; // Instantiates array if it doesn't exist
}
}
Without having $foo[$fooKey] instantiated as an array beforehand, we won't be able to do array_push without getting the Error 500. The shorthand $foo[$fooKey][] does the heavy work for us, checking if the provided element is an array, and if it isn't, it creates it and pushes the item in for us.
I know this is an old answer but it might be helpful for others to know that another difference between the two is that if you have to add more than 2/3 values per loop to an array it's faster to use:
for($i = 0; $i < 10; $i++){
array_push($arr, $i, $i*2, $i*3, $i*4, ...)
}
instead of:
for($i = 0; $i < 10; $i++){
$arr[] = $i;
$arr[] = $i*2;
$arr[] = $i*3;
$arr[] = $i*4;
...
}
edit- Forgot to close the bracket for the for conditional
No one said, but array_push only pushes a element to the END OF THE ARRAY, where $array[index] can insert a value at any given index. Big difference.
I need to get all the elements from a textarea in a HTML form and insert them into the MySQL database using PHP. I managed to get them into an array and also find the number of elements in the array as well. However when I try to execute it in a while loop it continues displaying the word "execution" (inside the loop) over a 1000 times in the page.
I cannot figure out what would be the issue, because the while loop is the only applicable one for this instance
$sent = $_REQUEST['EmpEmergencyNumbers'];
$data_array = explode("\n", $sent);
print_r($data_array);
$array_length = count($data_array);
echo $array_length;
while(count($data_array)){
echo "execution "; // This would be replaced by the SQL insert statement
}
you should use
foreach($data_array as $array)
{
//sql
}
When you access the submitted data in your php, it will be available in either $_GET or $_POST arrays, depending upon the method(GET/POST) in which you have submitted it. Avoid using the $_REQUEST array. Instead use, $_GET / $_POST (depending upon the method used).
To loop through each element in an array, you could use a foreach loop.
Example:
//...
foreach($data_array as $d)
{
// now $d will contain the array element
echo $d; // use $d to insert it into the db or do something
}
Use foreach for the array or decrement the count, your while loop
is a infinite loop if count is >0
I'm using a nestedsortable jQuery plugin that gives me the order/sort of the elements serialized.
And example of this serialitzation (root means parent_id=0):
id[1]=root&id[5]=1&id[2]=1&id[3]=1&id[4]=3
First thing I'll do is explode by &:
$serialized = "id[1]=root&id[5]=1&id[2]=1&id[3]=1&id[4]=3";
$exploded = explode("&", $serialized);
But I don't know then how to manage a id[1]=root or id[3]=1. How I can do it?
And another question. In this way I don't know which is how to store the order. When I've the exploded with in array like array("id"=>1, "parent"=>"root"); I've to store the order. I will do it with an index, but how I recognise nested levels?
An example:
$i = 0;
foreach($exploded as $explode)
{
//update every id in MySQL and set parent=$explode["parent"] and order=$i
$i++;
}
But if I've N levels, how I can have a index $i for every one of them?
Thank you in advance!
Rather than exploding, you could try parse_str()
<?php
parse_str("id[1]=root&id[5]=1&id[2]=1&id[3]=1&id[4]=3",$result);
print_r($result);
?>
From there you can work with the array.