This to me is the cleanest looking solution and I happen to really like it. Spread syntax allows an iterable such as an array expression or string to be expanded in places where zero or more arguments (for function calls) or elements (for array literals) are expected, or an object expression to be expanded in places where zero or more key-value pairs (for object literals) are expected. This means that you can use the map function to get an array of id's and then pass it into the max() function using the spread operator. If you were paying attention you already did that earlier using map. This means that all you have to do is get an array of id's and you can pass that into the max() function. If you dig into Math.max you will find out that it can take a list of numbers or an array of numbers. While I like the map and reduce approach much better than iterating over the array it still doesn't feel great to me. You can also use a combination of reduce and the next solution Math.max() if you want to. The difference here is using reduce is much faster. If you notice this is a similar approach to us using the forEach method, iterating over each element and comparing it to max. reduce ( ( max, character ) => ( character. Finally it needs to set a default value for max and that is what characters.id is doing. The callback method is looking at the character id and if it's greater than max it returns that, if not it returns max. Every time the callback function is called it will return a value and store it in max. You will define a accumulator which will accumulate the callback's return value. Here you are going to call reduce on the characters array. The reduce() method executes a reducer function (that you provide) on each member of the array resulting in a single output value. sort ( ( a, b ) => a - b ) = 444 ) Array.reduce If you wanted to get really fancy you can do all of that in a single statement. sort ( ( a, b ) => a - b ) assert ( sorted = 444 ) At this point you can just use the normal sort method on the array, grab the last element in the list and that is your max id. You will use the map method to create a new array that contains just the id's so you're no longer working with objects. The map() method creates a new array with the results of calling a provided function on every element in the calling array. So if you were going to take that approach here you can start with the map method. Whenever that red flag of iterating over an array comes up I immediatly ask myself is this something that map/filter/reduce can solve. What if you have one thousand or a million objects in the array? Any time that I start iterating over an array using some type of loop to perform som calculation that is a huge red flag for me. If you were to run this code it certainly works but it just doesn't seem right to me. My main objective every time I write code is to get something to work first and then improve upon it later. const characters = [ ) assert ( max = 444 ) Each character in the array is going to be an object that contains an id, first name and last name. Side note: If you haven't read that book yet, I highly recommend it. I recently read the book Bad Blood so I decided to use some of the characters from that book. Next you are going to create an array of characters. The first thing that I am going to do is to require the assert module from Node which gives us the ability to provide a simple set of assertion tests. I am using Node to run this example but you can just as easily use JavaScript and drop this into a web page. In this article I will walk you through a 4 different solutions. I wanted a quick and efficient way to look at all of the ids and find the max id. I had this array of objects and in each object I had an id. I was recently putting together a tutorial for some students and I came across an issue that I am sure we have all come across at one time or another. You can load multiple translation files and use the lang_code option to choose which language to use.How to find the max id in an array of objects in JavaScript Just include one of the files after the main JavaScript to Translation files are available in the i18n folder. Include query-builder.css in your page head and
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