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How to find the largest value of an array in an arraylist in JavaScript

I have an array with elements in the following format. I tried, I collected everything edtime

and put them in edtimearray

. I am trying to find the largest among the array values. I used something like this. but I get the message "the object does not support this action".

var edtimearray = [];
for (var i = 0; i <= obj.length - 1; i++) {
    edtimearray = obj[i].edtime;
    if (i == obj.length - 1) {
        var arrayMax = Function.prototype.apply.bind(Math.max, edtimearray);
    }
}
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2 answers


I think you can simplify this:

var max = Math.max.apply(Math, obj.map(function(o) { return o.edtime; }));

So, you start with an array of objects, and you want to get an array of property values ​​from those objects. JavaScript (unfortunately) does not have a standard "curl" method, so you use .map()

these property values ​​to construct an array.



Now what you want to do is call Math.max()

with these property values ​​as arguments like

var max = Math.max(value1, value2, ... )

What's included .apply()

. When you need a list of arguments but you have an array, .apply()

is your friend. So we just need to call Math.max()

with .apply()

- and pass in Math

as a value this

, because some native functions are picky about this - and then an array as the second argument.

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Here's a good way to get the largest element in an array:



var arr = []; // some array with values
arr.sort().reverse(); // sort array ascending order
var largestVal = arr[0];
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