I have an array of arrays in JavaScript that I'm storing some values in, and I'm attempting to find a way to clear the value within that array when the user removes the specified control from the page, however I'm not finding a good way to do this and anything I try doesn't seem to be working.
What is the best method for clearing the value in the array? I'd prefer the value to be null so that it's skipped when I iterate over the array later on.
I've tried to do MyArray[id][subid] = '' but that still is technically a value. I've also tried to do MyArray[id][subid].length = 0 but that doesn't seem to do anything either. Trying to grab the index and splice it from the array returns a -1 and therefore doesn't work either.
var MyArray;
window.onload = function(){
MyArray = new Array();
}
function EditValuesAdd(){
var Input = document.getElementById('Values-Input').value;
var ID = document.getElementById('FID').value;
var ValueID = ControlID(); // generate GUID
if (!MyArray[ID]) MyArray[ID] = new Array();
MyArray[ID][ValueID] = Input;
document.getElementById('Values').innerHTML += '<a href="#" id="FV-' + ValueID + '" onclick="EditValuesRemove(this.id)"/><br id="V-' + ValueID + '"/>';
}
function EditValuesRemove(id)
{
var ID = document.getElementById('FID').value;
document.getElementById(id).remove();
document.getElementById(id.replace('FV-', 'V-')).remove();
MyArray[ID][id.replace('FV-', '')] = '';
}
I've also tried to do an index of and then splice it from the underlying array but the index always returns -1.
var Index = MyArray[ID].indexOf(id.replace('FV-', ''));
MyArray[ID].splice(Index, 1);
Setting the length to zero has no effect either.
MyArray[ID][id.replace('FV-', '')].length = 0;
I would expect that one of the methods above would clear out the value and make it null so that it is skipped later on but all of the methods I've found and tried so far leave some non-null value.
What you need is an object (a Map), not an array (a list).
Here's a basic idea of how to do it :
MyArray = {};
....
if (!MyArray[ID]) MyArray[ID] = {}
MyArray[ID][ValueID] = Input;
...
delete MyArray[ID][id.replace('FV-', '')];
Check here for more information : https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object
In the end I used an array of objects MyArray = [] and then using splice/findindex to remove it from the array:
function RemoveItem(id)
{
var Index = MyArray.findIndex(a => a.ID == id.replace('FV-', ''));
MyArray.splice(Index, 1);
document.getElementById(id).remove();
document.getElementById('FVB-' + id.replace('FV-', '')).remove();
}
It doesn't solve the actual question asked but I don't know if there really is an answer since I was using arrays in the wrong manner. Hopefully this at least points someone else in the right direction when dealing with arrays and objects.
Related
good evening, I am trying to use a single value to search an array, and return the full line the said value is in.
The Array is set up like this in string form:
Xanax,Brand,Anxiety,Code
However, now I'm stuck with calling back only the Medication, and not the full line the Medication is in, sadly. I would like to be able to grab each variable in a line, and make them their own independent variables outside of the array so I can use them for something else.
this.importDataObject("MEDDIAGNOSISICD-10.txt", "C:/Users/dell/Documents/tab
excel/MEDDIAGNOSISICD-10.txt");
var oFile = this.getDataObjectContents("MEDDIAGNOSISICD-10.txt");
var cFile = util.stringFromStream(oFile, "utf-8");
var fileArray = cFile.split('\t');
var Med = this.getField("Medications 1");
var Index = fileArray.indexOf(Med.value);
var Call = fileArray[Index];
console.println(Call);
Any help would be wonderful!
It's because you are running the indexOf method on the whole array, you need to run it on the each value instead. Try a for loop before you check IndexOf method.
Like this:
var i, Index;
for (i = 0; i < fileArray.length; i++) {
Index = fileArray[i].indexOf(Med.value);
if(Index > -1) console.log('Your search is found in ' + fileArray[i] );
}
Note that, in here the variable Index will be 0 or larger if that search is successful. And will be of value -1 if no match is found.
I am new to js and I don't understand much of codes and conditions in js.
My question is simple but I need someone to give me a good example if possible as I know what I need but it is getting hard to implement that in code.
This is my code with 2 arrays where the data is coming from.
blind_tmp = '';
for (i=0; i<#All of Blind Relationship Link.length; i++){
blind_tmp = blind_tmp + '<p>[**' + #All of Element Title[i] + '**](' + #All of Blind Relationship Link[i] + ')'
};
What simple needed is that. I want merge records that are duplicates printed.
for example: if Blind Relationship link is AF44 and after 6 elements this AF44 comes again so I want both to be written like 1.AF44,2.AF44
while now it is writing the elements how they come along
example:
AF11,AF22,AF33,AF44,AF55,AF66,AF77,AF44
so in this example you see two AF44
I want them to be written like this
AF11,AF22,AF33,AF44AF44,AF55,AF66,AF77
any help with a code example is appreciated.
The idea is to iterate through each element in the blindRelationshipLink and store those elements in a temporary array which will be used to check the number of occurrence of an array element.
var blindRelationshipLink = ['AF11','AF22','AF33','AF11','AF44','AF44','AF55','AF66','AF77','AF11','AF22','AF11'];
var arrTemp = [];
var p = '';
blindRelationshipLink.forEach(function(arr){
var count = 0;
arrTemp.forEach(function(a){
if(arr === a)
count++;
});
arrTemp.push(arr);
if(count){
count++;
arr= arr + '.' + count;
}
p = p + arr + ',';
});
alert(p);
You test by running the code snippet.
This approach is not best but it may serve your purpose.
Here is a snippet
var elemArray = ['AF11', 'AF22', 'AF33', 'AF44', 'AF55', 'AF66', 'AF77', 'AF44']; // Array of elements
//A new array which which will contain elements which pass our case
var finalArray = [];
elemArray.forEach(function(item) { // loop through main array
// Check if element is present or else push the element
if (finalArray.indexOf(item) == -1) {
finalArray.push(item);
} else {
// if element is there find the index
var getIndex = finalArray.indexOf(item);
// remove the element, else there will be duplicate
finalArray.splice(getIndex, 1);
//concate the matched element
var newElem = item + item;
// push the element in specfic index
finalArray[getIndex] = newElem;
}
})
console.log(finalArray)
Current drawback with this code is what will happen if there are multiple repeated item in the main array. For example presence of AF33 more than twice.
DEMO
Very close but slightly more complex than this question I have an array and I want to obtain the index of the array of the first occurrence of a value of a given object of this array.
My array has several objects of integer and text, and has an id object of integers (which I call with this instruction wup[i].id).
[edit] The array comes from reading a csv file with header with papaparse.
wup = ["id", "cityName", etc ... ]
[20002, "Tokyo", etc ... ]
[20003, "Goiânia", etc ... ]
It is in this id object only that I want to find the input value and finally get the index of this input value. This is certainly using indexOf but how to focus the search only in the id object?
[edit] the instruction that fails is the following (try to find the occurrence of tn[iter].idOri in the array wup, that I expect to retrieve in the variable iOri):
var iOri = wup.indexOf(tn[iter].idOri);
Hoping it is clear enough.
There are lots of ways to do this, map your array down to a flat array of ids:
var myId = 3;
var ids = array.map(function(obj) {
return obj.id;
});
var index = ids.indexOf(myId);
A more succinct (and better - because it only requires one iteration) method would be to use Array.findIndex:
var myId = 3;
var index = array.findIndex(function(obj) {
return obj.id === myId;
});
With es6:
var myId = 3;
var index = array.map(obj => obj.id).indexOf(myId);
or
var myId = 3;
var index = array.findIndex(obj => obj.id === myId);
I have the following javascript code that does not work as I would expect it to. I have a list of checkboxes of which two of the items are "TestDuration" and "AssessmentScores". I'm trying to iterate through the list (which works fine) and have it add the values that are checked to the array.
var SAIndex = 0;
var SSIndex = 0;
var ScoresIndex = 0;
var SubAssessments = [];
var SubAssessmentScores = [];
//Get to the container element
var SSList = document.getElementById("islSubAssessmentScore_container");
//turn it into an array of the checkbox inputs
SSList = SSList.getElementsByTagName("input");
//create a temporary object to store my values
var tempPair = new Object();
//iterate through the checkbox lists
for(var i = 1; i < SSList.length;i++)
{
//if the value is checked add it to the array
if (SSList[i].checked)
{
var P = SubAssessments[SAIndex];
var V = SSList[i].value;
//tempPair.Parent = SubAssessments[SAIndex];
tempPair.Parent = P;
//tempPair.Value = SSList[i].value;
tempPair.Value = V;
//show me the values as they exist on the page
alert(tempPair.Parent + "|" + tempPair.Value);
SubAssessmentScores.push(tempPair);
//show me the values I just added to the array
alert(SubAssessmentScores.length-1 + "|" + SubAssessmentScores[SubAssessmentScores.length-1].Parent + "|" + SubAssessmentScores[SubAssessmentScores.length-1].Value);
//uncheck the values so when I refresh that section of the page the list is empty
SSList[i].checked = false;
}
}
//output the list of objects I just created
for (i = 0;i < SubAssessmentScores.length;i++)
alert(i + "|" + SubAssessmentScores[i].Parent + "|" + SubAssessmentScores[i].Value)
Now what happens is that when I iterate through the list I get the following alerts:
-first pass-
StudentID|TestDuration
0|StudentID|TestDuration
-second pass-
StudentID|AssessmentScores
1|StudentID|AssessmentScores
This is what I expect to output... However at the end of the code snippet when it runs the for loops to spit out all the values I get the following alerts...
0|StudentID|AssessmentScores
1|StudentID|AssessmentScores
I can't for the life of me figure out why it's replacing the first value with the second value. I thought it might be using a reference variable which is why I added in the P and V variables to try to get around that if that was the case, but the results are the same.
This is because you are adding the same variable every iteration of the loop.
Try changing your push like this:
SubAssessmentScores.push({
Parent: P,
Value: V
});
That said, I recommend you study a little more javascript and conventions in the language, for example your variable naming is frowned upon because you should only use capital letters on the beginning of a name for constructor functions.
A good book is Javascript the good parts by Douglas Crockford.
I'm trying to break up a string like this one:
fname=bill&mname=&lname=jones&addr1=This%20House&...
I want to end up with an array indexed like this
myarray[0][0] = fname
myarray[0][1] = bill
myarray[1][0] = mname
myarray[1][1] =
myarray[2][0] = lname
myarray[2][1] = jones
myarray[3][0] = addr
myarray[3][1] = This House
The url is quite a bit longer than the example. This is what I've tried:
var
fArray = [],
nv = [],
myarray = [];
fArray = fields.split('&');
// split it into fArray[i]['name']="value"
for (i=0; i < fArray.length; i++) {
nv = fArray[i].split('=');
myarray.push(nv[0],nv[1]);
nv.length = 0;
}
The final product is intended to be in 'myarray' and it is, except that I'm getting a one dimensional array instead of a 2 dimensional one.
The next process is intended to search for (for example) 'lname' and returning the index of it, so that if it returned '3' I can then access the actual last name with myarray[3][1].
Does this make sense or am I over complicating things?
Your line myarray.push(nv[0],nv[1]); pushes two elements to the array myarray, not a single cell with two elements as you expect (ref: array.push). What you want is myarray.push( [nv[0],nv[1]] ) (note the brackets), or myarray.push(nv.slice(0, 2)) (ref: array.slice).
To simplify your code, may I suggest using Array.map:
var q = "foo=bar&baz=quux&lorem=ipsum";
// PS. If you're parsing from a-tag nodes, they have a property
// node.search which contains the query string, but note that
// it has a leading ? so you want node.search.substr(1)
var vars = q.split("&").map(function (kv) {
return kv.split("=", 2);
});
For searching, I would suggest using array.filter:
var srchkey = "foo";
var matches = vars.filter(function (v) { return v[0] === srchkey; });
NB. array.filter will always return an array. If you always want just a single value, you could use array.some or a bespoke searching algorithm.
for (var i = 0; i < fArray.length; i++) {
nv = fArray[i].split('=');
myarray.push([nv[0],nv[1]]);
}
nv.length = 0; is not required, since you're setting nv in each iteration of the for loop.
Also, use var i in the for-loop, otherwise, you're using / assigning a global variable i, that's asking for interference.