javascript设计模式(一)职责链模式China of responsibility

表单请求搜索，验证，提示。表单提示验证请求模块

//请求模块
    var sendData=function(data,dealType,dom){
        var xhr=new XMLHttpRequest();
        var url='getData.php?mod=userInfo';
        xhr.onload=function(event){
            if((xhr.status>=200 && xhr.status<300)|| xhr.status==304){
                dealData(xhr.responseText,dealType,dom)
            }else{
//                请求失败
            }
            //拼接请求字符串
            for(var i in data){
                url+="&"+i+'='+data[i];
            }
            //发送请求
            xhr.open('get',url,true);
            xhr.send(null)
        }
    }
    //响应数据适配模块
    var dealData=function(data,dealType,dom){
        var dealType=Object.prototype.toString.call(data);
        //判断相应的数据处理对象
        switch (dealType){
            case 'sug':
                if(dealType==='[object Array]'){
                    return createSug(data,dom);
                }
                if(dealType==="[object Object]"){
                    var newData=[];
                    for(var i in data){
                        newData.push(data[i])
                    }
                    return createSug(newData,dom);
                }
                return createSug([data],dom);
            break;
            case "validata":
                return createValidataResult(data,dom);
            break;
        }
    }
    //创建组件模块
    //提示框组件
    var createSug=function(data,dom){
        var i= 0,
            len=data.length
            html="";
        for(;i<len;i++){
            html+="<li>"+data[i]+"</li>";
        }
        dom.parentNode.getElementsByTagName("ul")[0].innerHTML=html;
    }
    //校验组件
    var createValidataResult=function(data,dom){
        dom.parentNode.getElementsByTagName("span")[0].innerHTML=data;
    }

将复杂的功能拆分成单个独立的对象