IndexOf is missing a value in an array

Question

I realize that IndexOf will return a -1 when it doesn't find a value within an array, however, the value that I have it searching for is in the array. I have confirmed this by returning the value in the array with console.log

Here is some of my code (paraphrased for simplicity):

var xtiles = [];

function assignValue(tile) {
    xtiles.push(tile); //tile is 1 at this point
    checkArray();
}

function checkArray() {
    var temp = xtiles.indexOf(1);
    console.log(temp); //this returns a -1
    console.log(xtiles[0]); //this returns a 1
}

The variable 'temp' should return a 0 since there is a 1 in index 0 of the array xtiles. What am I missing here?

This is exactly what doesn't make sense. If I explicitly set it in the assignVaue function (xtiles[0] == 1) then the indexOf returns a 0. Is there some sort of conflict with the .push? — CdnXxRRODxX, Oct 28 '15 at 00:47
title must not equal 1, look here https://jsfiddle.net/9q3ahk13/ — stackoverfloweth, Oct 28 '15 at 00:47
is it possible that title is a string? that would result in a -1 if xtiles[0] = "1" and you're doing a search for the number 1 — stackoverfloweth, Oct 28 '15 at 00:48
You guys are right, I'm reading tile from a value in another function and thought it was returning an integer. I should have checked that first...thanks a lot guys! — CdnXxRRODxX, Oct 28 '15 at 00:51

score 0 · Answer 1 · answered Oct 28 '15 at 00:48

0

That's because the number 1 is not strictly equal to the string '1'.

indexOf() compares searchElement to elements of the Array using strict equality (the same method used by the ===, or triple-equals, operator).

References:

Array.prototype.indexOf()

answered Oct 28 '15 at 00:48

zerkms

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score 0 · Answer 2 · answered Oct 28 '15 at 02:12

0

If the content of the array are strings then you can perhaps search as follows:

var temp = xtiles.indexOf(1+""); // force 1 into a string

answered Oct 28 '15 at 02:12

MervS

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IndexOf is missing a value in an array

2 Answers2