//      Recherche la version anglaise de la page

//      extract front part of string prior to searchString

function getFront(mainStr,searchStr)

{

 foundOffset = mainStr.indexOf(searchStr)

 if (foundOffset == -1) 

 { 

   return null 

 } 

  return mainStr.substring(0,foundOffset)

} 

 

//      extract back end of string after searchString 

function getEnd(mainStr,searchStr)

{ 

  foundOffset = mainStr.indexOf(searchStr) 

  if (foundOffset == -1) 

  { 

    return null 

  } 

   return mainStr.substring(foundOffset+searchStr.length,mainStr.length)

} 

  

//      insert insertString immediately before searchString 

function insertString(mainStr,searchStr,insertStr)

{

  var front = getFront(mainStr,searchStr) 

  var end = getEnd(mainStr,searchStr) 

  if (front != null && end != null) 

  { 

    return front + insertStr + searchStr + end 

  } 

   return null 

}



//      remove deleteString 

function deleteString(mainStr,deleteStr)

{ 

  return replaceString(mainStr,deleteStr,"") 

}



//      replace searchString with replaceString 

function replaceString(mainStr,searchStr,replaceStr)

{

 var front = getFront(mainStr,searchStr)

 var end = getEnd(mainStr,searchStr) 

 if (front != null && end != null)

  {

     return front + replaceStr + end 

  }

  return null

}



//      Appel de la fonction



var premierefois = false

function RecherchePageAng()

{

 if (premierefois==false)

   {

    var adresse  = top.location.href;

    var francais = "fra";

    var anglais  = "ang";

    resultat = replaceString(adresse,francais,anglais);

    document.location.href=resultat

    window.open.location

    premierefois = true

   }

}