scroll.js

javascript的客户端脚本代码,用于网站上发布广告.相当不错的代码.

var bNetscape4plus = (navigator.appName == "Netscape" && navigator.appVersion.substring(0,1) >= "4");
var bExplorer4plus = (navigator.appName == "Microsoft Internet Explorer" && navigator.appVersion.substring(0,1) >= "4");
function CheckUIElements(){
      var yMenuFrom, yMenuTo, yButtonFrom, yButtonTo, yOffset, timeoutNextCheck;

      if ( bNetscape4plus ) { 
              yMenuFrom   = document["divMenu"].top;
              yMenuTo     = top.pageYOffset + 295; 
      }
      else if ( bExplorer4plus ) {
              yMenuFrom   = parseInt (divMenu.style.top, 10);
              yMenuTo     = document.body.scrollTop + 135; //距页面顶部的距离
      }

      timeoutNextCheck = 500;

      if ( Math.abs (yButtonFrom - (yMenuTo + 152)) < 6 && yButtonTo < yButtonFrom ) {
              setTimeout ("CheckUIElements()", timeoutNextCheck);
              return;
      }

      if ( yButtonFrom != yButtonTo ) {
              yOffset = Math.ceil( Math.abs( yButtonTo - yButtonFrom ) / 10 );
              if ( yButtonTo < yButtonFrom )
                      yOffset = -yOffset;

              if ( bNetscape4plus )
                      document["divLinkButton"].top += yOffset;
              else if ( bExplorer4plus )
                      divLinkButton.style.top = parseInt (divLinkButton.style.top, 10) + yOffset;

              timeoutNextCheck = 10;
      }
      if ( yMenuFrom != yMenuTo ) {
              yOffset = Math.ceil( Math.abs( yMenuTo - yMenuFrom ) / 20 );
              if ( yMenuTo < yMenuFrom )
                      yOffset = -yOffset;

              if ( bNetscape4plus )
                      document["divMenu"].top += yOffset;
              else if ( bExplorer4plus )
                      divMenu.style.top = parseInt (divMenu.style.top, 10) + yOffset;

              timeoutNextCheck = 10;
      }

      setTimeout ("CheckUIElements()", timeoutNextCheck);
}

function OnLoad()
{
      var y;
      if ( top.frames.length )
      if ( bNetscape4plus ) {
              document["divMenu"].top = top.pageYOffset + 135; 
              document["divMenu"].visibility = "visible";
      }
      else if ( bExplorer4plus ) {
              divMenu.style.top = document.body.scrollTop + 235;
              divMenu.style.visibility = "visible";
      }
      CheckUIElements();
      return true;
}
OnLoad();