javascript 菜单三级联动

// JavaScript Document




var arrTypes = new Array();


arrTypes[0] = [1,"儿童分类1",0];


arrTypes[1] = [2,"妇科分类2",0];


arrTypes[2] = [3,"内科分类3",0];




arrTypes[3] = [4,"儿科二级分类3",1];


arrTypes[4] = [5,"儿科二级分类4",1];


arrTypes[5] = [6,"妇科二级分类5",2];






arrTypes[6] = [7,"儿科三级分类7",4];


arrTypes[7] = [8,"儿科三级分类8",4];


arrTypes[8] = [9,"儿科三级分类9",5];


arrTypes[9] = [10,"儿科三级分类10",5];


arrTypes[10] = [11,"妇科三级分类11",6];


arrTypes[11] = [12,"内科二级分类12",3];


arrTypes[12] = [13,"独自一类",0];


document.write("<select name=type1 id=type1 onchange='changetype(this.value,2)'></select>");


document.write("<select name=type2 id=type2 onchange='changetype(this.value,3)' style="display:'none';"></select>");


document.write("<select name=type3 id=type3 style="display:'none';"></select>");




select1=document.getElementById("type1");


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




...{


if(arrTypes[i][2]==0)




...{


selectcurr = document.getElementById("type1");


newitem = new Option(arrTypes[i][1],arrTypes[i][0]);


selectcurr.options.add(newitem);


}


}


changetype(select1.options[0].value,2);


function changetype(uid,deep)




...{


selectcurr = document.getElementById("type"+deep);


if(selectcurr)




...{


var ln = selectcurr.options.length;


var len = 0;


while (ln--)




...{


selectcurr.options[ln] = null;


}




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




...{


if(arrTypes[i][2]==uid)




...{


newitem = new Option(arrTypes[i][1],arrTypes[i][0]);


selectcurr.options.add(newitem);


selectcurr.style.display='';


len++;


}


}




if(len==0)




...{


selectcurr.style.display='none';


selectcurr2 = document.getElementById("type3");


selectcurr2.style.display='none';


}


if(deep==2 && len>0)




...{


changetype(selectcurr.options[0].value,deep+1);


}


}


}