//==============================================================================
// OnOffイメージの変更
//------------------------------------------------------------------------------
//・指定されたイメージオブジェクトの画像をxxxOn/xxxOffで切り替える
//  On時にカーソルをpointerに変更する
//------------------------------------------------------------------------------
// imageObj  イメージオブジェクト
//------------------------------------------------------------------------------
// return    none
//==============================================================================
function changeOnOffImageButton(imageObj){
  var imageSource = imageObj.src;
  var imageSourceDirectory = imageSource.substring(0, imageSource.lastIndexOf("/") + 1);
  var imageName = imageSource.substring(imageSource.lastIndexOf("/") + 1, imageSource.lastIndexOf("."));
  var imageNameExtension = imageSource.substring(imageSource.lastIndexOf("."), imageSource.length);

  if(imageName.match(/(On?|\/)$/) == null){
    imageObj.src = imageSourceDirectory + imageName.substring(0,imageName.lastIndexOf('Off')) + "On" + imageNameExtension;
    imageObj.style.cursor = "pointer";
  }else{
    imageObj.src = imageSourceDirectory + imageName.substring(0,imageName.lastIndexOf('On')) + "Off" + imageNameExtension;
    imageObj.style.cursor = "none";
  }
}