I have an javascript array and I want to delete an element based on the value of the array, this is my array and this is what I have tried without success.
array = []
array.push (["Mozilla","Firefox",1.10])
index = array.indexOf(["Mozilla","Firefox",1.10])
array.splice(index, 1)
But it doesn't work, any idea¿?
You're trying to compare arrays, which are objects and have unique addresses. Your index variable is -1.
Try ['Mozilla','Firefox',1.10] === ['Mozilla','Firefox',1.10] in your console, you'll see that just because two arrays have the same values, it doesn't mean they are the same array.
What you need is a deep-equals style of comparison, that checks each value in the array, to see if two arrays have a likeness.
Take a look at lodash's isEqual function for an idea.
Here's a simple looping function:
function deepIndex(array, comparison) {
var i, j;
main:
for (i = 0; i < array.length; i++) {
if (Array.isArray(array[i])) {
for (j = 0; j < array[i].length; j++) {
if (array[i][j] !== comparison[j]) {
continue main;
}
}
return i;
}
}
}
var arr = [];
arr.push('string', ['Mozilla','Firefox',1.10], 'thing');
var index = deepIndex(arr, ['Mozilla','Firefox',1.10])
console.log(index, arr);
arr.splice(index, 1);
console.log(arr);Take a look at this:
// Array Remove - By John Resig (MIT Licensed)
Array.prototype.remove = function(from, to) {
var rest = this.slice((to || from) + 1 || this.length);
this.length = from < 0 ? this.length + from : from;
return this.push.apply(this, rest);
};
This is function, made by the Creator of JQUery. Basically you take the Index of one thing and than it is getting removed
Array.prototype.remove = function(from, to) {
var rest = this.slice((to || from) + 1 || this.length);
this.length = from < 0 ? this.length + from : from;
return this.push.apply(this, rest);
};
//Equals Function taken from:
//http://stackoverflow.com/questions/7837456/comparing-two-arrays-in-javascript
Array.prototype.equals = function (array) {
// if the other array is a falsy value, return
if (!array)
return false;
// compare lengths - can save a lot of time
if (this.length != array.length)
return false;
for (var i = 0, l=this.length; i < l; i++) {
// Check if we have nested arrays
if (this[i] instanceof Array && array[i] instanceof Array) {
// recurse into the nested arrays
if (!this[i].equals(array[i]))
return false;
}
else if (this[i] != array[i]) {
// Warning - two different object instances will never be equal: {x:20} != {x:20}
return false;
}
}
return true;
}
array = [];
array.push (["Mozilla","Firefox",1.10]);
array.push (["Microsoft","Spartan",1.0]);
array.push (["Safari","Safari",1.4]);
index = indexOfArr(array,["Mozilla","Firefox",1.10]);
array.remove(index, index);
document.getElementById("length").innerHTML = array.length;
for(var i = 0; i < array.length; i++){
document.getElementById("elems").innerHTML += "<br>"+array[i];
}
function indexOfArr(hay, needle){
for(var i = 0; i < hay.length; i++){
if (hay[i].equals(needle)){
return i;
}
}
return -1;
}<span id = "length"></span><br>
<span id = "elems">Elements:</span>You can use the fiter metodh, instead of indexOf.
Within the callback of that method, you can choose different approaches:
Use toString on the arrays and compare the two strings
Test for the length and the content, by iterating over the contained elements
... Continue ...
In any case using === will solve the problem, unless the object contained is exactly the same against which you are trying to match.
By the same, I mean the same. We are non speaking about having the same content, but to be the same instance.
Loop over your array and check the equality:
array = [];
array.push(["Mozilla", "Firefox", 1.10]);
for (var i = 0; i < array.length; i++) {
if (arraysEqual(array[i], ["Mozilla", "Firefox", 1.10])) {
array.splice(i, 1);
}
}
function arraysEqual(a, b) {
if (a === b) return true;
if (a === null || b === null) return false;
if (a.length != b.length) return false;
for (var i = 0; i < a.length; ++i) {
if (a[i] !== b[i]) return false;
}
return true;
}
JSFiddle: http://jsfiddle.net/ghorg12110/r67jts35/
Based on this question : How to check if two arrays are equal with JavaScript?
You can do something like this
array = []
array.push (["Mozilla","Firefox",1.10])
tempArray = array[0];
index = tempArray.indexOf("Mozilla","Firefox",1.10)
array.splice(index, 1)
You can build on this if you put for loop instead of hard coding.
["Mozilla","Firefox",1.10] == ["Mozilla","Firefox",1.10]returnsfalse