对Dom树的操作 appendChild ,createElement,childNodes,createTextNode

window.onload=function()...{


    //????


    var hello = document.getElementById('hello');


    hello.className="declared";


    


    var empty = document.getElementById('empty');


    addNode(empty,"reader of","br"); 


    addNode(empty,"Ajax in Action","br");


  


    var children = empty.childNodes;




    for(var i=0;i<children.length;i++)...{


        children[i].className="programe";


 


    } 


    empty.style.border='solid green 2px';


    empty.style.width='200px';


}






function addNode(ele,text,br)...{




    if(text==null)...{


        ele.appendChild(document.createElement("br"));




    }else...{


        var childEl =document.createElement("div");//?????


        ele.appendChild(childEl);


    


        var txtNode = document.createTextNode(text);//?????


        childEl.appendChild(txtNode);


        if(br!=null)


            ele.appendChild(document.createElement(br));


    }


 


}




//


var i=0;






function addListItemUsingInnerHTML(ele,text)...{


    var obj = document.getElementById(ele);


    obj.innerHTML+="<div class='programe'>"+text+"</div><br>";


    


}


//






function showEmpty(ele)...{


        var obj = document.getElementById(ele);


     




        if(obj!=null)...{




        if(obj.style.display==''||obj.style.display=='inline')...{


            obj.style.display='none';


            }




        else...{


            addNode(obj,"txt"+(i++),"br");


            obj.style.display='inline';


            


            }


        }


        


    }

 

Ajax封装状态,基础

 




/**//*    


    version:0.0.1 


    Date:2007.2.11 In China


    Mail:yanweiboy@hotmail.com


    


*/




var net =new Object();//????




net.READY_STATE_UNINITIALIZED=0;


net.READY_STATE_LOADING=1;


net.READY_STATE_LOADED=2;


net.READY_STATE_INTERACTIVE=3;


net.READY_STATE_COMPLETE=4;






net.ContentLoader=function(url,onload,onerror)...{//????


    this.url=url;


    this.req=null;


    this.onload=onload;


    this.onerror=(onerror) ? onerror: this.defaultError;


    this.loadXMLDoc(url);


}






net.ContentLoader.prototype=...{




    loadXMLDoc:function(url)...{




        if(window.XMLHttpRequest)...{


            this.req=new XMLHttpRequest();




        }else if(window.ActiveXObject)...{


            this.req=new ActiveXObject("Microsoft.XMLHTTP");


        }




        if(this.req)...{




            try...{


                var loader=this;




                this.req.onreadystatechange=function()...{


                    loader.onReadyState.call(loader);


                }


                this.req.open('GET',url,true);


                this.req.send(null);




            }catch(err)...{


                this.onerror.call(this);


            }


        }


    },


    




    onReadyState:function()...{


        var req = this.req;


        var ready = req.readyState;


        




        if(ready==net.READY_STATE_COMPLETE)...{


            var httpStatus=req.status;




            if(httpStatus==200||httpStatus==0)...{


                this.onload.call(this);




            }else...{


                this.onerror.call(this);


            }


        }


    },


    




    defaultError:function()...{


        alert("error fetching data!"


            +"  readyState: "+this.req.readyState


            +"  stats: "+this.req.status


            +"  headers: "+this.req.getAllResponseHeaders()


        );


    }


    


}