Passing array value between two different click events - javascript

How can I pass values ​​from an array from one event click to another with jQuery?
Here is an example of I want to do: the first click event adds or remove values from the array if the input checkbox is selected or not. In the second click I want to loop trough all the elements of this array.
var array=[];
$( "input" ).on( "click", function() {
var $input=$(this)
if($input.is(":checked")){
array.push($(this).val()); //append check box value to array if is selected
}
else{
array.pop($(this).val()); // remove check box value to array if is not selected
}
})
$('#cmd').click(function() {
for (i of array) {
console.log(array[i]); // loop trough all elements in array
...
});

Your code looks ok except two things. First for for (i of array). Using of will return actual value as i, but you are using value as index in array[i].
If you want use index then use for (let i = 0; i < array.length; i++) instead.
You can also use Array.prototype.forEach() but you can't break out of it's loop https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/forEach
Second thing is that .pop() doesn't support parameter. Use code below instead of .pop()
var index = array.indexOf($input.val());
if (index > -1) {
array.splice(index, 1);
}
If your event handlers are in different scope and #cmd handler can't see the array. You might use this little bit bad solution for sharing the array between scopes :)
$("input").on( "click", function() {
var array = $("#cmd").data("arr") || [];
var $input= $(this);
var value = $input.val();
if($input.is(":checked")){
array.push(value); /
} else {
var index = array.indexOf(value);
if (index > -1) {
array.splice(index, 1);
}
}
$("#cmd").data("arr", array);
});
$('#cmd').click(function() {
var array = $(this).data("arr") || [];
for (let value of array) {
console.log(value); // loop trough all elements in array
}
});

Related

How do I prevent two identical elements to be printed in a table?

I'm writing a javascript code, where the user should be able to search through dimension elements, which is displayed within a "pop-up" window with a table.
The code that displays the elements in the array looks like this:
$element.find("#myInput").on("qv-activate", function (){
let elemList = [];
self.backendApi.getData(requestList).then(function (dataPages) {
let elem = dataPages[0].qMatrix;
for(let i = 0; i < elem.length; i++){
elemList.push(elem[i][0].qText);
}
$(document).ready(function () {
$("#myInput").on("keyup", function () {
var value = $(this).val().toLowerCase();
for (var i=0; i<elemList.length; i++) {
if (elemList[i].toLowerCase().indexOf(value) >= 0){
$element.find('#searchTable').prepend('<tr><td id="searchElem">' + elemList[i] + '</td></tr>');
}
}
});
});
})
})
The only problem is, when I use the searchbar, it presents the element multiple times. Is there a way I can make sure, that the .prepend() only prepends if it is not the same value as before?
Some kind of; if element value is identical with the before prepended value, then don't prepend?
Hope it makes sense, and you have a solution to my problem.
Thanks!
Instead of calling prepend in the second for loop, make a new array and append elemList[i] to that.
Then use a solution from "Get all unique values in an array (remove duplicates)" to remove the duplicates from the array. For example, if values is your new array:
function onlyUnique(value, index, self) {
return self.indexOf(value) === index;
}
values = values.filter(onlyUnique);
Finally, loop through your new array and call prepend on each.

Remove duplicates in array separated by double commas in JavaScript

I have an array in JavaScript like this
var data = [,A_1_VII,VII,V2,,A_1_VII,VII,V2,,A_1_VII,VII,V2,,B_1_XIV,XIV,V3,,B_2_XVI,XVI,V3]
when I alert in JavaScript it gives as below
,A_1_VII,VII,V2
,A_1_VII,VII,V2
,A_1_VII,VII,V2
,B_1_XIV,XIV,V3
,B_2_XVI,XVI,V3
But I want like this which is duplicates removed array
var unique_data = [,A_1_VII,VII,V2,,B_1_XIV,XIV,V3,,B_2_XVI,XVI,V3]
On alert it should give like this
,A_1_VII,VII,V2
,B_1_XIV,XIV,V3
,B_2_XVI,XVI,V3
First Thing your array contains string as a constant that's not going to work.
Secondly, if all of you value are strings you can do it as follows:
var data =[,"A_1_VII","VII","V2",,"A_1_VII","VII","V2",,"A_1_VII","VII","V2",,"B_1_XIV","XIV","V3",,"B_2_XVI","XVI","V3"];
var uniqueArray = data.filter(function(item, pos) {
return data.indexOf(item) == pos;
})
alert(uniqueArray);
Assuming the variables in your array are well defined, you can clean it up and remove duplicates with a for loop:
var data [/* ... */];
var unique_data = [];
for(let i = 0; i < data.length; i++) {
if (data[i] && unique_data.indexOf(data[i]) === -1) {
unique_data.push(data[i]);
}
}
Please note that the code above assumes that your array contains non-object types, otherwise the solution would need to use something more sophisticated than indexOf().
You can create your unique function to remove duplicate entry and empty value from array like this.
var data =[,"A_1_VII,VII","V2,,A_1_VII","VII","V2",,"A_1_VII","VII","V2",,"B_1_XIV,XIV","V3",,"B_2_XVI,XVI,V3"]
var unique_data = uniqueList(data);
alert(unique_data);
function uniqueList(list) {
var uniqueResult = [];
$.each(list, function(i, e) {
if ($.inArray(e, uniqueResult) == -1 &&$.inArray(e, uniqueResult)!="")// chech for unique value and empty value
uniqueResult.push(e);
});
return uniqueResult ;
}
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>

Traversing list items using array method

I am using the values input by the user to perform this action.
Here is the full code: https://jsfiddle.net/7196dfyz/
This is part of the code where the elements are traversed, where I'm having trouble:
var lists = $ul.getElementsByTagName("li");
for (var i = 0; i < lists.length; ++i) {
if (lists[i] == value) {
$("ul").css("background-color","black");
}
}
The first input should take the value in some li
and the second input should take the respective parent ul class name.
I think this is what you're looking for. (Here is an updated jsfiddle):
function func() {
var key = $("#key").val();
var value = $("#entry").val();
var $ul = $("." + key);
var lists = $ul.find("li");
for (var i = 0; i < lists.length; ++i) {
console.log($(lists[i]).text(), value);
if ($(lists[i]).text() === value) {
$(lists[i]).css("background-color","black");
}
}
}
You have several issues:
$ul.getElementsByTagName is not a valid function. Because $ul at this point is a jQuery array-like object, it wont work. You'd need to do $ul[0].getElementsByTagName, or simply use jQuery's find() like my example above.
You're trying to compare lists[i] to value, which happens to be an HTML element. When comparing to a string, it will return <li>Say</li> which will never match anything you type in. Using $(lists[i]).text() should get you what you need.
$("ul").css("background-color","black");: You were setting every ul to black if a match was found. I assume you only want to match the one that was matched. $(lists[i]).css("background-color","black"); fixes this.
You can even simplify this entire function down to this:
function func() {
var key = $("#key").val();
var value = $("#entry").val();
$("." + key).find("li").filter(function() {
return $(this).text() === value;
}).css("background-color","black");
}
Broken down:
$("." + key): Find the ul that has the class of key.
.find("li") Find all list items within each unordered list found.
.filter(...) For each element in this list, and return to me only the items that match my criteria: $(this).text() === value.
And finally .css("background-color","black"): Set all the background colors to black of the list items that were returned from the filter() function.

Remove item from array in JavaScript

Seen this question a lot, but cannot find something that's what i'm looking for.
onClick I push an item to an array I have, however, if there's 3 items in my array I don't want to be able to push items anymore.
var selectedData = [];
I set my empty variable.
var index = selectedData.indexOf(3);
I then get the index of my array which is 3
if (index > 3) {
selectedData.splice(index, 1);
}
Then within my if statement I say, if my index which is 3, is bigger then 3, then splice at index and remove one.
selectedData.push(TheThing);
I then push TheThing to my array if the if statement above isn't true.
However, I have a variable var arrayLength = selectedData.length; that grabs the length, and when I console log it, it starts at 0 and splices items anything after 4. Not 3.
Any idea what i've done wrong or misunderstood?
Thanks
More full example of my code
var selectedData = [];
myElement.on('click', function() {
var index = selectedData.indexOf(3);
if (index > 3) {
selectedData.splice(index, 1);
}
var arrayLength = selectedData.length;
console.log(arrayLength, 'the length');
});
So in short, onClick check my array and remove anything after the third that gets added into my array.
Do you want this to behave as a stack or a queue?
So your code here:
var index = selectedData.indexOf(3);
Is not grabbing the 3rd index - its grabbing the first index where it sees 3, or -1 if it doesn't. Replace your if statement with,
if (selectedData.length > 3) {
selectedData.pop() // removes last element (stack)
// or
selectedData = selectedData.slice(1) //remove first element (queue)
}
I think you need to try var arrayLength = selectedData.length -1;
You start at 0 like a normal array, but don't you start with an empty array?
Plus when you use .length, it returns the true count of the array or collection not a 0 index.
`
you can override push() method of your array like this:
var a = [];
a.push = function(){}
or like this
a.push = function (newEl){
if(this.length <3){
Array.prototype.push.call(this, newEl)
}
}
This is not complete example because push() can take many arguments and you should to handle this case too
var index = selectedData.indexOf(3); simply give you the index of the element of the array that has value 3
Example
selectedData = [ 0, 3 , 2];
alert( selectedData.indexOf( 3 ) ); // this will alert "1" that is the index of the element with value "3"
you can use this scenario
var selectedData = [];
myElement.on('click', function() {
//if selectedData length is less than 3, push items
});
This could work.
myElement.on('click', function() {
if(selectedData.length > 3){
selectedData = selectedData.splice(0, 3);
}
console.log(selectedData.length, 'the length');
});

unset javascript array for

I've been trying at this for hours now and I thought it would be really simple;
Using javascript I basically want to iterate through an array, get the current value of the index and then unset this value from the array. I've found splice() is supposed to work for this however I don't seem to be able to empty the array, there is always one value left on the arrary
var filtered = array("up", "down", "left");
function resetTags(){
var length = filtered.length;
for(i=0; i <= length; i++){
filtered.splice(i,1);
}
}
EDIT::
I'll try to explain in a bit more detail:
I'm basically trying to keep track of a listed of selected class values which are obtained
from when an item is clicked:
var filtered = array();
jQuery("li a").click(function () {
tag = jQuery(this).text();
addFiltered(tag);
});
function addFiltered(param){
var inArray = jQuery.inArray(param,filtered);
if(inArray > -1){
//param is in array, so we want to remove it from the filtered array
filtered.splice(index, 1);
});
}else{
//param isn't in array, so we want to add it to the array
filtered.splice(0, 0, param);
});
}
}
If you want to empty the array, set it to be an empty array directly:
filtered = [];
If you want to use the values before emptying the array, simply iterate before that without removing values and clear it when you are done.
What do you stand to gain by messing with convoluted solutions?
the array was defined incorrectly. That is why the code didn't excute
var filtered = ["up", "down", "left"];
function resetTags(){
var length = filtered.length;
for(i=0; i <= length; i++){
filtered.splice(i,1);
}
}
To remove items one by one:
var a = [1,2,3,4,5];
while (a.length > 0 ) {
a.splice(0,1);
}
http://jsfiddle.net/89hkH/
Well, you're incrementing. Have you tried decrementing?
var filtered = new Array("up", "down", "left");
function resetTags(){
var length = filtered.length;
for(i = length; i >= 0; i--){
filtered.splice(i,1);
}
}
This should make sure the final element is spliced.
I basically want to iterate through an array, get the current value
of the index and then unset this value from the array.
for(i=0; i <= length; i++){
filtered.splice(i,1);
}
I don't think you are clearly defining (or perhaps don't know), what you're trying to do.
Are you trying to write a pop(n) method such that:
var a = [1,2,3,4]
var result = pop(3, a)
result == [ 1, 2, 4]
Or are you just trying to walk an array and get the first element off every time? If so, you're doing it wrong. That's just a shift()
var filtered = ["up", "down", "left"]
for(i = 0 ; i<= filtered.length; i++)
{
alert(filtered);
filtered.shift();
alert(filtered);
}

Categories