Question

I’m new to JavaScript and would like some constructive criticism regarding a code snippet. This example searches an associative array using a value input by the user. Is there a better way to approach this problem; what would be a more elegant solution while still using an associative array? Thanks.

var myObject = [
    {id: 1, word: 'ant', definition: 'an insect with eight legs.'}, 
    {id: 2, word: 'cake', definition: 'a food made with flour and sugar.'},
    {id: 3, word: 'house', definition: 'a building where a family lives.'},
];

function search(arg){
    var count = 0;
    for (var i = 0; i <= myObject.length; i++) {
        if (myObject[i].word == arg) {
            document.write(myObject[i].id + " - " + myObject[i].word + " - " + 
                               myObject[i].definition + "<br>"); 
            count += 1;
        }
        else {
            if (count != 1 &&
                    myObject[i].word != arg &&
                    i == myObject.length - 1) {

                document.write("NOT FOUND!");
            }
        }
    }
}

var arg = prompt("Search For An Entry");
if (arg != null && arg.length != 0) {
    search(arg);
} 

Answer 1

Looks pretty good. The only thing I could suggest (and it’s a very small improvement) would be to cache the length of your associative array before looping over it, like this:

for (var i = 0, len = myObject.length; i < len; i++) {

You could also move that last if statement to check if the search parameter hasn’t been found outside of the for loop, like this:

for (var i = 0, len = myObject.length; i < len; i++) {
    if (myObject[i].word == arg) {
        document.write(myObject[i].id + " - " + myObject[i].word + " - " + myObject[i].definition + "<br>");
        count += 1;
    }

    if(i == len-1 && count > 0) return;
}

document.write("NOT FOUND!");

This code exits the search function if it’s found any of the search params before it ends the for loop. This means that any code exited outside the for loop only runs if the search results in “not found”.