how to convert a string to an array in php
<p>how to convert a string in array in php i.e</p>

<pre> $str="this is string";</pre>

<p>should be like this</p>

<pre> arr[0]=this
      arr[1]=is
      arr[2]=string </pre>

<p>The <pre>str_split($str, 3);</pre> split the string in 3 character word but i want to convert the string after whitespace in an array.</p>
