How do I choose a random value from an array with JavaScript? [duplicate]

Question

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JavaScript: Getting random value from an array

I have an external js with the following line:

var postmessage = "hi my favorite site is http://google.com";

but is there a way to pick a site a random from an array so like this

var postmessage = "hi my favorite site is +'random'";

random= http://google.com, http://yahoo.com, http://msn.com, http://apple.com

how do i make it work?

Answer 1

var sites = new Array('http://www.google.com', "http://www.stackoverflow.com")

var postmessage = "hi my favorite site is" + sites[Math.round(Math.random()*(sites.length-1))];

First stick all of your sites in an array. Then get a random number from the array length (the -1 is because an array is zero indexed and the length that is returned starts at 1)