Ajax space and paging functions used in Kexun Business Edition_javascript skills

The ajax space and paging functions used in the commercial version of Kexun SQL, their js code learning is very good
//ajax control
function PageAjax(){
var xhrObj=null;
if(window.XMLHttpRequest)
                                                        Obj=newActiveXObject ("Microsoft.XMLHTTP");
}
catch(e1)
try{
xhrObj=new ActiveXObject("MSXML2. catch(e2){
try{
xhrObj=new ActiveXObject("MSXML3.XMLHTTP");
}
catch(e3){
alert("Failed to create Ajax:" e3)
}
}
}
}
else
{
alert("Unrecognized browser");
}
return xhrObj;
}

function Page(curPage,labelid,classid,installdir,url,refreshtype,specialid)
{
this.labelid=labelid;
this.classid=classid;
this.url=url;
if (labelid.substring(0,5)=="{SQL_")
{
var slabelid=labelid.split('(')[0];
slabelid=slabelid.replace("{","");
this.c_obj="c_" slabelid;
this.p_obj="p_" slabelid;
}
else
{
this.c_obj="c_" labelid;
this.p_obj="p_" labelid;
}
this.installdir=installdir;
this.refreshtype=refreshtype;
this.specialid=specialid;
this.page=curPage;
loadData(1);
}
function loadData(p)
{ this.page=p;
var xhr=new PageAjax();
xhr.open("get",installdir url "?labelid=" escape(labelid) "&classid=" classid "&refreshtype=" refreshtype "&specialid=" specialid "&curpage=" p, true);      eval('document.all. ' c_obj).innerHTML="

Connecting to server...
";
                                                                                                                                                                                                                                                                🎜>                                                                                                                             ";
              }
              else if(xhr.readyState==4)
              {
             if (xhr.status==200)
             {
                  var pagearr=xhr.responseText.split("{ks:page}")
                  var pageparamarr=pagearr[1].split("|");
                  count=pageparamarr[0];    
                  perpagenum=pageparamarr[1];
                  pagecount=pageparamarr[2];
                  itemunit=pageparamarr[3];   
                  itemname=pageparamarr[4];
                  pagestyle=pageparamarr[5];
                  getObject(c_obj).innerHTML=pagearr[0];
                  pagelist();
             }
            }
       }
    xhr.send(null); 
}
function getObject(id) 
{
    if(document.getElementById) 
    {
        return document.getElementById(id);
    }
    else if(document.all)
    {
        return document.all[id];
    }
    else if(document.layers)
    {
        return document.layers[id];
    }
}

function pagelist()
{
 var n=1;    
 var statushtml=null;
 switch(parseInt(this.pagestyle))
 {
  case 1:    
     statushtml="共" this.count this.itemunit " 首页 上一页 下一页 尾页 页次:" this.page "/" this.pagecount "页 " this.perpagenum this.itemunit this.itemname "/页";
        break;
  case 2:
     statushtml="" this.pagecount "页/" this.count this.itemunit " 9 7 ";
     var startpage=1;
     if (this.page==10)
       startpage=2;
     else if(this.page>10)
       startpage=eval((parseInt(this.page/10)-1)*10 parseInt((this.page)) 2);
      for(var i=startpage;i          if (i==this.page)
           statushtml ="" i " "
          else
            statushtml ="" i " "
            n=n 1;
          if (n>10) break;
      }
     statushtml ="8 :";
     statushtml="" statushtml "";
    break;     
  case 4:
     statushtml="共" this.pagecount "页/" this.count this.itemunit this.itemname " 9 7 ";
      for(var i=this.page;i          if (i==this.page)
           statushtml ="" i " "
          else
            statushtml ="[" i "] "
            n=n 1;
          if (n>10) break;
      }
     statushtml ="8 :";
    break;     
  case 3:
     statushtml="第" this.page "页 共" this.pagecount "页   > >> " this.perpagenum this.itemunit this.itemname "/页";
   break;
 }
statushtml =" No. ";
for(var i=1;i if (i==this.page)
statushtml =" " i "";
else
statushtml ="" i "";
} }
statushtml ="page";
getObject(this.p_obj).innerHTML=statushtml;
}
function homePage()
{
if(this.page==1)
alert("It’s already the home page! ")
else
loadData(1);
}
function lastPage()
{
if(this.page==this.pagecount)
alert("already It’s the last page! ")
else
loadData(this.pagecount);
}
function previousPage()
{
if (this.page>1)
loadData(this.page-1);
else
alert("Already the first page");
}

function nextPage()
{
if(this.page loadData(this.page 1);
else
alert("The last page has been reached");
}
function turn( i)
{
loadData(i);
}