Scroll textarea upwards/downwards on clicking prev and next hyperlinks in web page
<p>I want to show a hyperlinks "prev" "next".
Clicking on "next hyperlink should scroll textarea to next location. 
Clicking on "prev" hyperlink should scroll textarea to previous location.</p>

<p>The locations to jump in textarea are known e.g. line: 10, then line 40 , 50 , 70 , 101 , ....
textarea has a fixed height.</p>
