I'm trying to convert a js array to string. This string should be a value of a hidden input as so:
<input type="hidden" ng-model="myIndicationsString" />
In the controller:
$scope.myIndicationsString = $scope.productIndications.toString();
The problem is, it changes the array to a string value so when a change is needed to occur in $scope.productIndications it fails to do so.
Is there a method like toString() without changing the actual element? only returning a string result?
Thanks before
Try using JSON.stringify to generate a string representation of your array, like this:
$scope.myIndicationsString = JSON.stringify($scope.productIndications);
This function will not modify the original array, so you'll be able to continue using that as before. If you need to turn that string that stringify returns back into an array, you can use JSON.parse to do so.
I am not sure what you are exactly asking but join might be what you are looking for.
Let say your array is array = [John, Steve, Rob, Mary, Tom], then what you can do is:
array.join(',') \\John,Steve,Rob,Mary,Tom
array.join(' ') \\John Steve Rob Mary Tom
array.join('And') \\JohnAndSteveAndRobAndMaryAndTom
Slightly confused what you are asking, however, assuming you are using angularjs, you can make an identical copy of a scope variable as to maintain the state of the original variable.
var test = [1, 2, 3],
test2;
angular.copy(test, test2);
test2 should now be an identical copy that you can manipulate, without affecting test.
Related
I have a JSON file that was processor generated with lines like this
jsonData: "{data: [350.23,250.32,150.34,340.50,236.70,370.45,380.55]}"
I can target the 'jsonData' object but that returns everything within the double quotes as a string.
I tried ...dataset[0].jsonData[8] which returns the '3' from the first value. I guess I could throw the mixed strings into a JS function and use regex to remove the extra stuff, but thats probably the hackyest way to do this.
Whats the easiest way to target the values only?
If you want to interact with it like the list I would consider something like
var list = jsonData.split("[")[1].split("]")[0].split(",")
Console.log(list);
The console reads:
[
'350.23', '250.32',
'150.34', '340.50',
'236.70', '370.45',
'380.55'
]
From here you can use list[3] to get 340.50
If you don't want to spend the time fixing your JSON just do this:
let values = "{data: [350.23,250.32,150.34,340.50,236.70,370.45,380.55]}".split(',').map(_ => _.replace(/[^0-9.]/g,''))
console.log(values)
Basically I have a complex object that retrieves the GPT API (google publisher tag) with this function:
googletag.pubads().getSlots();
The object value is something like this:
I need to know if there is a way to compare the value of each property with an X value without getting a problem of recursivity (because the object is huge and i need to to that validation several times)
Also, I tried to convert that object into a JSON with JSON.stringify(), and then tried to get the value with a regex, faster, but with this option, I have the problem with Cyclic Object Value.
Any suggestions ?
it's more simple. try it to convert it into an array and later use a filter for comparative with your value.
var objGoogle = {};
var arrayObjectGoogle = [objGoogle];
var filter = arrayObjectGoogle.filter(function(obj){
obj.yourAttr == yourValue; });
this will give you a second array with the values found it. later, index the array for pick up the value do you need.
I'm learning to program in Javascript and I'd like some help/clarification.
I declared an array that contains animal names. I defined a function that I use to split a string in two. Then I create an empty object literal and add an animal and corresponding breed. I'm trying to invoke the separateWords function in the object literal, but I need some clarification. Here's my code:
var myPets = ["Bengal Bobcat", "Beagle"];
var separateWords = function (string) {
return string.split(" ");
};
var nameCollection = {};
nameCollection.cat = separateWords(myPets[0]);
nameCollection.dog = myPets[1];
nameCollection.fish = null;
When I enter console.log(nameCollection) I get the following:
Object {cat: Array[2], dog: “Beagle”, fish: null}
cat: Array[2]
0: "Bengal"
1: "Bobcat"
length: 2
However, when I enter console.log( separateWords(myPets[0])), I see:
[“Bengal”, “Bobcat”]
I don’t understand why the value of cat shows up as Array[2].
The console displays it as Array[2] as it would be (potentially) unreadable if it expanded it fully. One way to see everything is to stringify it using JSON.stringify which goes through each item in the object recursively and calls toString() on it:
var myPets = ["Bengal Bobcat", "Beagle"];
var separateWords = function (string) {
return string.split(" ");
};
var nameCollection = {};
nameCollection.cat = separateWords(myPets[0]);
nameCollection.dog = myPets[1];
nameCollection.fish = null;
document.body.textContent = JSON.stringify(nameCollection);
You are assigning to cat the result of the separateWords() function call, passing myPets[0] as a parameter.
separateWords() returns an array and with the myPets[0] input it returns a new array with the "Bengal" and "Bobcat" values splitted by the whitespace.
The split() function is the one creating an array with the splitted values and this result is returned by your separateWords() function, which also is the value assigned to the cat object member.
Each browser implements its console like it wants.
So your browser decided to implement the behavior you describe.
If you don't like it, propose a better idea to the developers of this browser. Or use another browser.
I am going to assume you are using Chrome Developer Tools or Firebug.
Developer tools condenses arrays and objects into easily readable lines you then inspect further with. What I mean is, you push the little arrow next each line in the console log to further inspect each object. I will use pictures to explain this.
Here I am assigning an array and then assigning an element in an object to that array as so:
As you can see when I log the object it show's an Array[2] rather than expand the array. In this next picture I then expand the array to inspect it.
Why is this exactly? My first thought is ease of readability. If you have an app that is complex and you have numerous debugging console logs, you can see all the logs on single lines making it easier to hunt down specific logs. As well, if you have a very large and complex object, it is arguably easier to read all the root elements on each line without expanding all the objects and arrays found within that object recursively.
String.prototype.split() returns an array containing the two values in the string which have been split. Read through this.
nameCollection.cat = separateWords(myPets[0])[0]; // nameCollection.cat == Bengal
nameCollection.cat = separateWords(myPets[0])[1]; // nameCollection.cat == Bobcat
This is simply how javascript (and many other languages) work. When you try to print "nameCollection" javascript doesn't automatically do a nice job of printing the cat array. Instead, it simply prints some type related information, which in this case is saying "cat" is an array of length 2.
The combination of my methods of declaring an array, adding elements to the array and applying the method toString() does not work. Essentially I enter a certain number (between one and five) values to textvariables : fontVorto1, fontVorto2, fontVorto3 ……… in the html-part of the document.
When I decide on leaving the remaining textelements empty, I click on a button, to assign them to an array, by way of the following function:
function difinNombroFv () {
var fontVortoj = new array();
fontVortoj[0] = document.getElementsByName("fontVorto1")[0].value;
fontVortoj[1] = document.getElementsByName("fontVorto2")[0].value;
fontVortoj[2] = document.getElementsByName("fontVorto3")[0].value;
……………….
and put them together in a string:
x = fontVortoj.toString();
document.getElementsByName("fontVorto")[0].value = x;
(the extra variable x is not needed) to enable me sending them to the next document, where I want to unserialize them with
$fontVortoj = unserialize($_POST["fontVorto"]);
I tested the method toString() by insering an alert(x), but the result was that I got for x the value of "fontVorto1" only.
I met solutions with JSON, jQuery etc., but I never used those "languages", only HTML, JavaScript, PHP.
Will my Christmas day be spoiled because of this simple problem ;>)?
couple of things to note:
1. var fontVortoj = new array(); . here new array() is not correct. it should be:
var fontVortoj = new Array();
now if you call fontVortoj.toString(), then it will convert the array and return a string with array elements separated by comma.
you can rebuild the array from the string in php by using "explode" function.
you can rebuild the array from the string in javascript by using "split" function.
Apparently I misunderstood the question to begin with.
To serialize an astray, you can use .join()
By default, it will give you the values, joined by commas.
To deserialize, use .split()
If there's a chance that there might be commas in your values, choose a more elaborate string for joining:
var ar = ["a", "b"];
var serialized = ar.join("|"); // "a|b"
var deserialized = serialized.split("|"); //["a", "b"]
The string that you use for joining and splitting can be as long as you like.
If you want to be completely covered against any values, then you need to look at JSON.stringify() & JSON.parse(). But that had browser compatibility issues.
The following code causes both elements from id 0 to be set to -, even though I want only one to be set to -1. Am I just creating a reference to the labelArray, or is something else?
labelArray.sort(compare);
valueArray = labelArray;
valueArray[0] = '-1';
labelArray[0] = '-';
All help is appreciated.
UPDATE (2019): It's been several years since I first did this post, and ES6 is used pretty much universally. So, I wanted to come back and add that, instead of using the slice() method recommended in the accepted answer, you can instead use array destructing in the following to make a copy:
valueArray = [...labelArray];
Yes. Both valueArray and labelArray reference the same underlying array. To make a copy, use slice():
valueArray = labelArray.slice(0);
NOTE: Slice() only copies 1 level deep, which works fine for primitive arrays. If the array contains complex objects, use something like jQuery's clone(), credit #Jonathan.
Am I just creating a reference to the labelArray […] ?
Yes, exactly. valueArray and labelArray still identify the same object, which hasn't been copied.
valueArray is just a reference to labelArray.
What you want to do is clone the array. You can do this using jQuery.clone() or a similar cloning function.