Please help - split string into array and do a RegExp search in the array

I have been trying to sort this out by myself but it seems like I just can't figure to work it out correctly.

Suppose, I have a string like this-

 var string="Where are you and Iam so sorry I cannot sleep I cannot dream tonight";

Code (markup):

Here, lets assume that the string that I want to search for it is Where

var search= new RegExp["^Where$"];

Code (markup):

I'm sure the object split() has got to do something with string and then do a testing.

Like this

var array=new array();
array=string.split(" ");

if(search.test(array))
{
document.write('true');
}

Code (markup):

Despite all my efforts to make it work, I just can't.

In php, we could have easily split the string into arrays using explode and call the function

if(in_array($search,$array))
{
echo "true";
}

Code (markup):

Please help(I'm just not very familiar with javascript) .Thanks

 

How about this?

var string="Where are you and Iam so sorry I cannot sleep I cannot dream tonight";
if (string.indexOf("Where") != -1) document.write("true");

Code (markup):