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JavaScript

Posted by Andrew Falkowski
Andrew Falkowski
708 Points

Randomizer

I want to make something that displays a random string from an array. I have been out of practice and I want to start up again. I would just need some markdown and that would suffice. This will be incorporated into a website.

1 Answer

Erik McClintock
Erik McClintock
45,783 Points
Erik McClintock
Erik McClintock
45,783 Points

Andrew,

This could be done rather easily using Math.random(), constraining it to generate a number between 0 and your array's highest index value. You could build a function that generates the number and then displays the appropriate string from your array based on the randomized index value.

Hope this helps!

Erik

Andrew Falkowski
Andrew Falkowski
708 Points

What if it isn't a number I want to display, would Math.random() still work? For example the string is: ("A", "A Sharp", "B").

Erik McClintock
Erik McClintock
45,783 Points
Erik McClintock
Erik McClintock
45,783 Points

Andrew,

Yes; Math.random() will generate a number which you can store in a variable, and then you pass that variable in for the index of your array.

So, for example, whereas normally if you wanted to print the second value (at index 1) of an array, you could do the following:

var myArray = ["A", "A Sharp", "B"];
console.log("The second value of this array is: " + myArray[1]);

Using Math.random(), you would instead first generate a random number and store it in a variable, and then instead of passing 1 (or 0 or 2 or whatever) into your array's index, you would pass the variable.

You're not using Math.random() to display a number, you're simply using it to generate a random number (which is what you're looking for) to be able to tell the array "Hey, I want you to give me a random string, located at the index that Math.random() generated for me".

Does this make any more sense?

Erik

Andrew Falkowski
Andrew Falkowski
708 Points

Yes it does thanks, though I want it to display the string on the webpage for the user. Could you give me some help with that?

Erik McClintock
Erik McClintock
45,783 Points
Erik McClintock
Erik McClintock
45,783 Points

Andrew,

For that, you'll want to look into DOM access and manipulation, via JavaScript methods such as getElementById(), and then altering that element's innerHTML.

Erik