import UnityEngine.UI;
import System;
...
function OnMouseDown()
{
var path = 'Reports/';
   var nam = 'report_'+inputname.text+'.html';

SaveTextFile(path+data+'_'+nam, content_html    );
System.Diagnostics.Process.Start(path+data+'_'+nam);

}

function SaveTextFile ( fileName : String, fileContent : String ) {
     var sw : StreamWriter = new StreamWriter ( fileName );
     sw.Write ( fileContent );
     sw.Close ();
   }