Develop Reference

foreach Statements with a function

ok I am trying to answer a question and learning to code. regarding an array and using foreach statements the function must remain as this "function animalNames" must stay somewhere but apparently, I am doing something wrong because I get it returned as undefined. even through it produces the correct array back could someone look at it and let me know what i have done wrong.
attached is a picture of the code and array and question that i answered. this is how i wrote my function.
const displayNames = [];
zooAnimals.forEach(function animalNames(element){
var display = "name: " + element.animal_name + ", " + "scientific: " + element.scientific_name
displayNames.push(display);
})
console.log(displayNames);
again i get the correct array back and the data looks correct...but animalNames comes back as undefined...i cannot remove this portion i am to keep it there but i do not know what to do with it.

try this, it defines a function animalNames as separate function
const displayNames = [];
const zooAnimals = [
{animal_name:"Jackel",scientific_name:"Canine"}
]
function animalNames({animal_name, scientific_name}){
return `name: ${animal_name}, scientific: ${scientific_name}`
}
zooAnimals.forEach((element)=>{
displayNames.push(animalNames(element));
})
console.log(displayNames);

I believe you are following this challenge. In this case, make sure to read the instructions properly:
The zoos want to display both the scientific name and the animal name in front of the habitats.
Use animalNames to populate and return the displayNames array with only the animal name and scientific name of each animal.
displayNames will be an array of strings, and each string should follow this pattern: "name: {name}, scientific: {scientific name}"
So from the instructions you are expected to create a function animalNames() that creates an array named displayNames and returns this array from within your function animalNames(). The array displayNames contains strings of the sturcture name: animal_name, scientific: scientific_name.
// you could set zooAnimals as a required parameter in your function
// but as it is defined in the same file you can access it directly as well
function animalNames() {
const displayNames = [];
// you have to do the forEach on zooAnimals here
zooAnimals.forEach(animal => displayNames.push(`name: ${animal.animal_name}, scientific: ${animal.scientific_name}`))
// return an array
return displayNames;
}
The way you did it, the function animalsName() is an anonymous function that only exists within the zooAnimals.forEach() call. Therefore, it is undefined.

how to get string 'Sugar&Jaggery, Salt' via <a> in codeigniter?

plz anyone me i m beginner in codeigniter in herf passing url with string but the whole can't get in
controller & can't accepting as sting so what shold i do for it plz someone help me
//Here is html code which pass sting value
index.php/Home/product_show?type='Sugar&Jaggery , Salt'">Sugar & Jaggery , Salt
//controller get sting in type variable but on Sugur got not whole sting and pass type variable to model
public function product_show(){
$type = $_GET['type'];
die(var_dump($type));
$data['testdata']= $this->Globle_model->get_multiple_record($type);
$this->load->view('display_product',$data);
}
//model type variable check the subcategory from database and return to controller
public function get_multiple_record($type){
$this->db->where_in('Subcategory_name',$type);
$get_data = $this->db->get('productmaster');
return $get_data->result_array();
}
//o/p
get this much of string(6) "'Sugar"

Please follow the below way to get all your string into the controller into
$_GET['type'] variable.
Combine all your strings into a single variable using _ into href
Example :
Sugar & Jaggery , Salt
In the controller, I have created one array() with variable subcategory_type .In which key is coming from the view but its value from the database.
Example :
function get_product_type(){
$get_info = $this->input->get();
$subcategory_type = array(
"Sugar_Jaggery_Salt" => "Sugar&Jaggery , Salt"
);
$type_arr = $subcategory_type[$get_info['type']];
$data['testdata']= $this->Globle_model->get_multiple_record($type_arr);
$this->load->view('display_product',$data);
}
In model,
function get_multiple_record($type_array){
$this->db->where_in('Subcategory_name',$type_array);
$get_data = $this->db->get('productmaster');
return $get_data->result_array();
}
Try this and update me in case of anything.

delete user from json table in js

So I'm a beginner to js and I have a table of users in a json file and I'm making an account delete feature. I have a find set up to find the user and it works fine but I can't figure out how to make it delete the user from the file, any help would be appreciated!
Json:
{
"users": [
{
"name": "ImBattleDash",
"Id": "780748c5d4504446bbba3114ce48f6e9",
"discordId": "471621420162744342",
"dateAdded": 1548295371
}
]
}
JS:
function findJson() {
fs.readFile('./linkedusers.json', 'utf-8', function (err, data) {
if (err) message.channel.send('Invalid Code.')
var arrayOfObjects = JSON.parse(data)
let findEntry = arrayOfObjects.users.find(entry => entry.discordId == myCode)
let linkEmbed = new Discord.RichEmbed()
.setTitle('Account unlinked!')
.setDescription('Link your account by friending "BattleDash Bot" on Fortnite and then input the code you get messaged by typing "!link <code>"!')
.setColor('#a900ff');
message.channel.send({embed: linkEmbed});
})
}
EDIT: Not sure if it's an array or a table I don't know a lot about json

You need to use:
Array#find to find a given user by some given criteria.
Array#indexOf to get the index of the found user in users
Array#splice to drop one element starting from the index given by Array#indexOf:
const input = {
"users": [
{
"name": "ImBattleDash",
"Id": "780748c5d4504446bbba3114ce48f6e9",
"discordId": "471621420162744342",
"dateAdded": 1548295371
}
]
}
const removeUser = (criteria, users) =>
users.splice (users.indexOf (users.find (criteria)), 1)
removeUser (
({ Id, discordId }) =>
Id == '780748c5d4504446bbba3114ce48f6e9'
&& discordId == '471621420162744342',
input.users
)
// Output: 0 <-- User has been removed!
console.log(input.users.length)
About persisting the change, it's just about calling JSON.stringify (input) and then just write the contents to the desired output file. See this other Q&A: Writing files in Node.js

With great help from Cat and Matias I came up with this code that works!
function findJson() {
fs.readFile('./linkedusers.json', 'utf-8', function (err, data) {
if (err) message.channel.send('Invalid Code.')
var arrayOfObjects = JSON.parse(data)
let findEntry = arrayOfObjects.users.find(entry => entry.discordId == myCode)
const input = arrayOfObjects;
const removeUser = (criteria, users) =>
users.splice (users.indexOf (users.find (criteria)), 1)
removeUser (
({ Id, discordId }) =>
Id == findEntry.Id
&& discordId == findEntry.discordId,
input.users
)
console.log('unlinked')
fs.writeFile('./linkedusers.json', JSON.stringify(arrayOfObjects, null, 4), 'utf-8', function(err) {
if (err) throw err
console.log('Done!')
})
let linkEmbed = new Discord.RichEmbed()
.setTitle('Account unlinked!')
.setDescription('Link your account by friending "BattleDash Bot" on Fortnite and then input the code you get messaged by typing "!link <code>"!')
.setColor('#a900ff');
message.channel.send({embed: linkEmbed});
})
}

Here's a quick tutorial for you:
"Users" would be either an array (using []) or a javascript object (using {}), your choice. There won't be any actual tables unless you use a database instead of a JSON file (although if your JSON expression is as simple as your example, you could almost think of it as a table.) -- And actually, a third option would be to use the javascript Map type, which is like a beefed-up object, but I won't address that here.
While using an array would make it a bit easier to retrieve a list of data for all users (because arrays are simpler to iterate through), using an object would make it considerably easier to retrieve data for a single user (since you can directly specify the user you want by its key instead of needing to loop through the whole array until you find the one you want.) I'll show you an example that uses an object.
The individual user in your sample code is an example of a javascript object. JSON lets you convert an object to a string (for storage, I/O, and human readability) and back to an object (so javascript can understand it). You use the JSON.stringify() and JSON.parse() methods, respectively for these conversions. The string has to be JSON-formatted or this won't work, and your example is almost in JSON format.
To comply with JSON formatting, you could structure a Users object as follows. (Of course we're looking at the stringified version because mere humans can't easily read an "actual" javascript object):
"Users": { // Each individual user is a property of your users object
"780748c5d4504446bbba3114ce48f6e9": // The Id is the key in the "key/value pair"
{ // The individual user object itself is the value in the key/value pair
// Id is duplicated inside user for convenience (not necessarily the best way to do it)
"id": "780748c5d4504446bbba3114ce48f6e9",
"name": "ImBattleDash", // Each property of the user is also a key/value pair
"discordId": "471621420162744342", //Commas separate the properties of an object
"dateAdded": "1548295371" // All property values need double quotes for JSON compatibility
}, // Commas separate the properties (ie the individual users) of the users object
"446bbba3114ce48f6e9780748c5d4504": // This string is the second user's key
{ // This object is the second user's value
"id": "446bbba3114ce48f6e9780748c5d4504",
"name": "Wigwam",
"discordId": "162744342471621420",
"dateAdded": "1548295999"
}
}
Once you retrieve the string from storage, you convert it to an object and delete a user as follows. (This is broken down into more steps than necessary for clarity.):
let usersObject = JSON.parse(stringRetrievedFromFile);
let userId = "780748c5d4504446bbba3114ce48f6e9";
let userToModifyOrDelete = usersObject[userId];
delete userToModifyOrDelete;
To change the user's discordId instead, you would do:
let discordId = userToModifyOrDelete.discordId; // Not necessary, just shows how to retrieve value
let newDiscordId = "whateverId";
userToModifyOrDelete.discordId = newDiscordId;
And you'd convert the object back into a string to store in your file with:
JSON.stringify(usersObject);
Hopefully that's almost all you need to know about JSON!

How to get all php array index from javascript?

I have a php file where I saved all language string. This is the content:
function lang($phrase)
{
static $lang = array(
'step_one' => 'First step',
'step_two' => 'Second step',
... and so on ...
);
return $lang[$phrase];
}
Essentially, when I load a javascript file I want store all array index in a variable like this:
var Lang = <?php echo json_encode(lang()); ?>;
this code line is inserted in a script, this script is available in a php file. Now before of execute this line I have imported the php file where all string translation is available. What I'm trying to achieve, is get all index of this array, in the variable Lang.
Actually I can load a single string traduction from php like this:
lang('step_one');
but how I can save this array in javascript variable?

You can use array_keys to retrieve all array keys. To do that you need your function to return the whole array on request. You can do that with leaving the argument ($phrase) empty and do an if condition with empty in your lang function. You also need to set a default value for $phrase in your function to not raise any errors if you don't pass an argument to the function.
echo json_encode(array_keys(lang());
And the function:
function lang($phrase = "")
{
static $lang = array(
'step_one' => 'First step',
'step_two' => 'Second step',
... and so on ...
);
if(empty($phrase)) {
return $lang;
} else {
if(isset($lang[$phrase])) { //isset to make sure the requested string exists in the array, if it doesn't - return empty string (you can return anything else if you want
return $lang[$phrase];
} else {
return '';
}
}
}
I also added isset to make sure the requested element exists in your language array. This will prevent raising warnings.

Dynamic Associative Array Creation in Javascript from JSON

It sounds a lot more complicated than it really is.
So in Perl, you can do something like this:
foreach my $var (#vars) {
$hash_table{$var->{'id'}} = $var->{'data'};
}
I have a JSON object and I want to do the same thing, but with a javascript associative array in jQuery.
I've tried the following:
hash_table = new Array();
$.each(data.results), function(name, result) {
hash_table[result.(name).extra_info.a] = result.(name).some_dataset;
});
Where data is a JSON object gotten from a $.getJSON call. It looks more or less like this (my JSON syntax may be a little off, sorry):
{
results:{
datasets_a:{
dataset_one:{
data:{
//stuff
}
extra_info:{
//stuff
}
}
dataset_two:{
...
}
...
}
datasets_b:{
...
}
}
}
But every time I do this, firebug throws the following error:
"XML filter is applied to non-xml data"

I think you can use the JSON response as an associative array. So you should be able to go directly in and use the JSON.
Assuming you received the above example:
$('result').innerHTML = data['results']['dataset_a']['dataset_two']['data'];
// Or the shorter form:
$('result').innerHTML = data.results.dataset_a.dataset_two.data;
Understand that I haven't tested this, but it's safer to use the square brackets with a variable than it is to use parenthesis plus the name with the dot accessor.
Your example is failing because of some convoluted logic I just caught.
$.each(data.results), function(name, result) {
hash_table[result.(name).extra_info.a] = result.(name).some_dataset;
});
Now, the foreach loop goes through the variable data.results to find the internal elements at a depth of 1. The item it finds is given to the lambda with the key of the item. AKA, the first result will be name = "datasets_a" item = object. Following me so far? Now you access the returned hash, the object in item, as though it has the child key in name ... "datasets_a". But wait, this is the object!
If all else fails... write your result JSON into a text field dynamically and ensure it is formatted properly.

Why would you want to change an array into another array ?-)
-- why not simply access the data, if you want to simplify or filter, you can traverse the arrays of the object directly !-)

This works. Just dump it into a script block to test.
d = {
'results':{
'datasets_a':{
'dataset_one':{
'data':{
'sample':'hello'
},
'extra_info':{
//stuff
}
},
'dataset_two':{
///
}
///
},
'datasets_b':{
///
}
}
}
alert(d.results.datasets_a.dataset_one.data.sample)
I hope this pasted in correctly. This editor doesn't like my line breaks in code.
d = {
'results':{
'datasets_a':{
'dataset_one':{
'data':{
'sample':'hello'
},
'extra_info':{
//stuff
}
},
'dataset_two':{
///
}
///
},
'datasets_b':{
///
}
}
};
alert(d.results.datasets_a.dataset_one.data.sample)