I have a list of values that I want to dynamically assign to another list of values:
var activeMachines = [41,44,46]
for(i = 0; i < activeMachines.length; i++){
var temp + activeMachines[i] = document.getElementById("tempData"+activeMachines[i]);
var humid + activeMachines[i] = document.getElementById("humidData"+activeMachines[i]);
var time + activeMachines[i] = document.getElementById("timeData"+activeMachines[i]);
}
What I am hoping to achieve is that this loop would create 6 new variables in total:
temp41 = document.getElementById("tempData41");
temp44 = document.getElementById("tempData44");
...
Above is not working. I have read some other posts suggesting using arrays, but I think I need to somehow dynamically create a dictionary, and I can't seem to get the syntax right to achieve this. any suggestions?
Anytime you're struggling to dynamically define variable names it's an indication that you should step back and reconsider your data structures. It's almost always the wrong choice that leads to difficult, messy code.
In this case it looks like you have three things that have an id and a temp, humidity and time property. This is exactly what objects are for.
For example you might represent the data like:
let data = { machine_41: {temp: 40, humid: 10, time: 200},
machine_44: {temp: 30, humid: 15, time: 500},
} // etc
Now all your data is in one place and you can access it with simple properties:
data.machine_41.temp
To go from your array of numbers to this object is simple with reduce():
var activeMachines = [41,44,46]
let data = activeMachines.reduce((obj, machineID) => {
// some fake data
temp = 20 // or document.getElementById etc..
humidity = 10
time = 600
obj['machine_'+machineID] = {temp, humidity, time}
return obj
}, {})
console.log("machine_41 humidity:",data.machine_41.humidity)
console.log(data)
This might not be the exact data structure you need (maybe it's better as an array for example), but this approach will serve you better than trying to create a bunch of individual variables.
You can use the window object for doing that, however, I recommend you to create your own object to store those "variables" as properties within that new key-value object.
var activeMachines = [41,44,46]
var obj = {};
for(i = 0; i < activeMachines.length; i++){
obj['temp' + activeMachines[i]] = document.getElementById("tempData"+activeMachines[i]);
obj['humid' + activeMachines[i]] = document.getElementById("humidData"+activeMachines[i]);
obj['time' + activeMachines[i]] = document.getElementById("timeData"+activeMachines[i]);
}
Try this
var activeMachines = [41,44,46];
var output = {};
for(i = 0; i < activeMachines.length; i++){
output["temp" + activeMachines[i]] = document.getElementById("tempData"+activeMachines[i]);
output["humid" + activeMachines[i]] = document.getElementById("humidData"+activeMachines[i]);
output["time" + activeMachines[i]] = document.getElementById("timeData"+activeMachines[i]);
}
console.log(output);
All your variables are define in this variable.
Access like output['temp41']
You can use an object and create properties instead of variables.
var context = {};
for (i = 0; i < activeMachines.length; i++) {
context[`temp${activeMachines[i]}`] = document.getElementById("tempData"+activeMachines[i]);
}
And the access those data with context.temp41 or context["temp41"]
Related
Currently, I have an empty new object and I want to populate values from an existing object to new object because I want to use an object with only limited properties from the existing object (e.g. I only want the four properties instead of eight).
Here's how I am doing the mapping so far:
const newObject: any = {};
for (let i = 0; i < this.PRODUCT_DATA.length; i++) {
newObject._productSkuKey = this.PRODUCT_DATA[i]._productSkuKey;
newObject._storeKey = this.itemPriceForm.get('location').value;
newObject._price = this.PRODUCT_DATA[i]._price;
newObject._status = this.PRODUCT_DATA[i]._isActive;
this.updatedProducts.push(newObject);
}
So far, it looks to be storing the values from the existing object to newObject. However, it is only saving the last object values and not the different values from the object. How can I fix this to save all values (not just the last values for every object in the array)?
You need to make a copy of that before pushing in array
const newObject: any = {};
for (let i = 0; i < this.PRODUCT_DATA.length; i++) {
newObject._productSkuKey = this.PRODUCT_DATA[i]._productSkuKey;
newObject._storeKey = this.itemPriceForm.get('location').value;
newObject._price = this.PRODUCT_DATA[i]._price;
newObject._status = this.PRODUCT_DATA[i]._isActive;
this.updatedProducts.push(Object.assign({}, newObject));
// Or
// this.updatedProducts.push({ ...newObjec });
}
Or Simply create object inside loop. I love to use Array.prototype.forEach and Array.prototype.map
this.updatedProducts = this.PRODUCT_DATA.map(({_productSkuKey, _price, _isActive})=> ({
_productSkuKey,
_storeKey: this.itemPriceForm.get('location').value,
_price,
_status: _isActive
});
Avoid declaring newObject as 'const'. This is an updated code that works for me.
//avoid using a const, as you cannot override it
let newObject: any = {};
for (let i = 0; i < this.PRODUCT_DATA.length; i++) {
newObject._productSkuKey = this.PRODUCT_DATA[i]._productSkuKey;
newObject._storeKey = this.itemPriceForm.get('location').value;
newObject._price = this.PRODUCT_DATA[i]._price;
newObject._status = this.PRODUCT_DATA[i]._isActive;
this.updatedProducts.push(newObject);
//after pushing the object, empty all the current contents
newObject={};
}
I'm pretty new (a few weeks in) to js and have a question about an incremental game I'm developing. My issue has to do with creating an array from an object I have and then fetching a property of the object, which is used in a compare statement and updated in my HTML.
I have the following object called UPGRADES:
var UPGRADES = {
newClothes: {
name: "New Clothes",
desc: "Give your bums a new look and some more motivation! \n Bum
production bonus: 100%",
moneyCost: 1000,
scienceCost: 10,
requiredScience: 10,
buildingAffected: BUILDINGS.bumBuilding,
upgVal: 2,
id: 'newClothes'
},
//{upgrade 2}
//{upgrade 3 etc.}
}
For one part of my code I need to go through each element of UPGRADES, return the nth object WITHIN "upgrades" (with newClothes as index 0), and then call (Nth index.scienceCost).
So far I've done the following:
var numBuildings = objectLength(BUILDINGS);
var numUpgrades = objectLength(UPGRADES);
function checkVisiblityOnUpgrades () {
var upgArray = [];
for (var a = 0; a < numUpgrades; a++) {
upgArray[a] = Object.keys(UPGRADES)[a].toString();
console.log(UPGRADES.upgArray[a]);
if (UPGRADES.upgArray[a].requiredScience <= resources.science) {
var idString = upgArray[a].id.toString();
getId(idString.concat("Button")).style.visibility = "visible";
getId(idString.concat("MoneyCostDisp")).innerHTML =
numFormat(upgArray[a].moneyCost);
getId(idString.concat("ScienceCostDisp")).innerHTML =
numFormat(upgArray[a].scienceCost);
}
}
}
I get this error along with it:
Uncaught TypeError: Cannot read property '0' of undefined
at checkVisiblityOnUpgrades (game.js:268)
at update (game.js:290)
268 is console.log(UPGRADES.upgArray[a]);
I was wondering how I would actually go about grabbing the values of the object I wanted. I'm creating an array in checkVisibilityOnUpgrades() so I can iterate through each upgrade with a for loop.
Another question I have is: If I was going to store 100+ instances of upgrades, would it be better to switch UPGRADES to an array rather than its own object? That way I could grab values a lot more easily.
You can drastically simplify your initial logic there with Object.entries:
Object.entries(UPGRADES).forEach(({ key, thisUpgradeObject }) => {
// `key` references the outer property, eg., 'newClothes'
// `thisUpgradeObject` references the inner object
});
So
Object.entries(upgArray).forEach(({ key, obj }) => {
const {
requiredScience,
id,
moneyCost,
scienceCost,
} = obj;
if (requiredScience < resources.science) return;
const idString = id.toString();
getId(idString.concat("Button")).style.visibility = "visible";
getId(idString.concat("MoneyCostDisp")).innerHTML = numFormat(moneyCost);
getId(idString.concat("ScienceCostDisp")).innerHTML = numFormat(scienceCost);
});
I see the problem here:
You create an array called upgArray, but then try to access UPGRADES.upgArray which is undefined. What you want to write there is likely UPGRADES[upgArray[a]].
function checkVisiblityOnUpgrades () {
var upgArray = Object.keys(UPGRADES);
for (var a = 0; a < numUpgrades; a++) {
if (UPGRADES[upgArray[a]].requiredScience <= resources.science) {
var idString = UPGRADES[upgArray[a]].id.toString();
getId(idString.concat("Button")).style.visibility = "visible";
getId(idString.concat("MoneyCostDisp")).innerHTML =
numFormat(UPGRADES[upgArray[a]].moneyCost);
getId(idString.concat("ScienceCostDisp")).innerHTML =
numFormat(UPGRADES[upgArray[a]].scienceCost);
}
}
}
I have a job to refractor strings to start using json so they can just pass json objects. So I have made array of names and then I'm trying to go through and make key and values but I'm getting an error in the console that it cant find x of no value. Can someone point me in the right direction?
var newName = ['ManagingOrg', 'ActiveOrg', 'Severity', 'SeverityClassification', 'WorkQueue', 'TicketState',................ to long to post];
$().each(newName, function (key, value) {
key = newName[this];
value = newValues[this] = $('#' + key).val();
newArray = [key][value];
newArray = JSON.stringify(newArray);
alert(newArray);
$('.results').html(origArray[TicketNumber]);
});
I'm assuming you have "newValues" and "origArray" defined elsewhere?
In any case you'll need to at least adjust the following:
"$().each" should be $.each
"newArray" should be defined outside and you should use newArray[key] = value
you don't have a variable "TicketNumber" defined and so you should wrap "TicketNumber" in quotes
this is a reserved word so you shouldn't use it in "newName[this]" or "newValues[this]"
I suggest using a for loop instead of $.each() based on what you're trying to do inside.
https://msdn.microsoft.com/en-us/library/bb299886.aspx
var origArray = [];
var newName = ['ManagingOrg', 'ActiveOrg', 'Severity', 'SeverityClassification'
];
for (var i = 0; i < newName.length - 1; i++) {
var object = {};
object[newName[i]] = newName[i];
object = JSON.stringify(object);
origArray.push(object);
}
I'm trying to populate an array from a JSON feed. My code looks something like this:
// multiple arrays
var linje_1 = []
var linje_2 = []
// loop from json feed to populate array
for( var i = 0; i < data.length; i++) {
// I'm trying to "build" the array here. I know for sure that data[i] is good value that match the suffix of the array.
arrayname = 'linje_'+data[i];
arrayname.push({ label: data[i].x_+''+sid[a]+'', y: data[i].y_+''+sid[a]+'' })
}
Does anybody have any suggestions on how to solve the above?
The problem is that the code will not accept arrayname, but if I change and hardcode linje_1, everything works as expected.
When you define a variable arrayname = 'linje_'+data[i]; then its type is String. Strings are not arrays, you can't treat them like array, they don't have array methods.
If you want to dynamically construct the name of the variable, the best thing you can do is to use object and its keys:
var lines = {
linje_1: [],
linje_2: []
};
for (var i = 0; i < data.length; i++) {
var arrayname = 'linje_' + data[i];
lines[arrayname].push({ label: data[i].x_ + sid[a], y: data[i].y_ + sid[a]});
}
Also note, that I cleaned up the code a little (things like data[i].x_ + '' + sid[a] + '').
You're pushing data to a String, not an array. Try this:
window[arrayname].push(/* ... */);
if your variables are declared in the scope of the window, they can be referenced in multiple manners:
myArray
window.myArray
window['myArray'] // You want this one
You're using the same variable for an array and string.
arrayname = 'linje_'+data[i];
arrayname.push({ label: data[i].x_+''+sid[a]+'', y: data[i].y_+''+sid[a]+'' })
The variable arrayname is defined as a string, but then you call the push method which is only a method for arrays.
jQuery.get("ChkNewRspLive.php?lastmsgID=" + n, function(newitems){
//some code to separate values of 2d array.
$('#div1').append(msgid);
$('#div2').append(rspid);
});
Let's say the value of newitems is [["320","23"],["310","26"]]
I want to assign "320" and "310" to var msgid.
I want to assign "23" and "26" to var rspid.
How to do that?
I tried to display newitems and the output is "Array". I tried to display newitems[0] and the output is blank.
If I redeclare var newitems = [["320","23"],["310","26"]]; it works. So I guess the variable newitems from jQuery.get is something wrong. Is it I cannot pass the array from other page to current page through jQuery directly?
Regarding the array on other page, if echo json_encode($Arraytest); the output is [["320","23"],["310","26"]] but if echo $Arraytest; the output is Array. How do I pass the array from other page to currently page by jQuery.get?
I don't totally understand the question but I'm going to assume you want the values in an array, as two values can't be stored in one (scalar) variable simultaneously.
jQuery.get("ChkNewRspLive.php?lastmsgID=" + n, function(newitems){
//some code to separate values of 2d array.
var msgid = [],
rspid = [];
for( i = 0 ; i < newitems.length ; i++){
msgid[msgid.length] = newitems[i][0];
rspid[rspid.length] = newitems[i][1];
}
//msgid now contains ["320","310"]
//rspid now contains ["23","26"]
});
Bear in mind those are in the function scope. If you want to use them outside of that scope instantiate them outside. see: closure
You can use pluck from underscore.js: http://documentcloud.github.com/underscore/#pluck
var msgid = _(newitems).pluck(0)
var rspid = _(newitems).pluck(1)
Try this:
function getArrayDimension(arr, dim) {
var res = [];
for(var i = 0; i < arr.length; i++) {
res.push(arr[i][dim]);
}
return res;
}
var newitems = [["320","23"],["310","26"]];
var msgid = getArrayDimension(newitems, 0);
var rspid = getArrayDimension(newitems, 1);
msgid and rspid are arrays holding the 'nth' dimention.
Tnx