js的一个简单的联动

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[b]1. 前面下拉框的改变触发后面下拉框的改变。[/b]
function change (value){
var s2=document.getById("max");
value=Integer.parseInt(value);
switch(value){
case( 0 ):
removeOp(s2);
break;


case(1):
removeOp(s2);
s2.options.add(new Option("",0));
s2.options.add(new Option("1",1));
s2.options.add(new Option("2",2));
s2.options.add(new Option("3",3));
s2.options.add(new Option("4",4));
break;


case(2):
removeOp(2);
s2.options.add(new Option("",0));
s2.options.add(new Option("2",2));
s2.options.add(new Option("3",3));
s2.options.add(new Option("4",4));
break;


case(3):
removeOp(s2);
s2.options.add(new Option("",0));
s2.options.add(new Option("3",3));
s2.options.add(new Option("4",4));
break;


case(4):
removeOp(s2);
s2.options.add(new Option("",0));
s2.options.add(new Option("4",4));
break;

case(5):
removeOp(s2);
s2.options.add(new Option("",0));
s2.options.add(new Option("5",5));
s2.options.add(new Option("6",6));
s2.options.add(new Option("7",7));
break;


case(6):
removeOp(s2);
s2.options.add(new Option("",0));
s2.options.add(new Option("6",6));
s2.options.add(new Option("7",7));
break;

case (7):
removeOp(s2);
s2.options.add(new Option("",0));
s2.options.add(new Option("7",7));
break;


default:
removeOp(s2);
s2.options.add(new Option("",0));
}

}


function removeOp (s1){
for(var i=s1.options.length-1;i>=0;i--){
s1.removechild(s1.options[i]);

}
}

<html:select property="work_cnt_min" onchange="change(this.value);">


[b]2.取到value后面的值（星期一...）[/b]

function getValues(){
var s=document.getElementById("day").value;
var cc=s.options[s.selectedIndex].text;
alert(cc);

}


<select id="day">
<option value="1"> 星期一</option>
<option value="2" >星期二</option>
<option value="3">星期三 </option>
<option value="4">星期四</option>
<select/>


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