通用二级下拉菜单(改进版)

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<title>通用二级下拉菜单(改进版) - 51windows.Net</title>
<meta http-equiv="Content-Type" content="text/html; charset=gb2312">
<meta name="author" content="haiwa">
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<body>
<script language="JavaScript">
<!--
function TwoSelectInit(so,dv1,dv2){
	var o1=so.o1;var o2=so.o2;var allstr=so.str;var dt1=so.dt1;var dt2=so.dt2;var selectonce=so.selectonce;
	var _s = "*|^@";
	var s1=new Array(),v1=new Array(),s2=new Array(),v2=new Array();
	var s1i = 0,s2i = 0;
	if(dt1!=""){
		if(!selectonce){allstr=dt1+_s.charAt(1)+_s.charAt(0)+allstr;}
		else{allstr=dt1+_s.charAt(1)+dt2+_s.charAt(0)+allstr;}
	}
	aa=allstr.split(_s.charAt(0));
	for(aai=0;aai<aa.length;aai++){
		aaa=aa[aai].split(_s.charAt(1));
		tmps1 = aaa[0].split(_s.charAt(3));
		s1[aai] = tmps1[0];v1[aai] = (tmps1.length==2)?tmps1[1]:tmps1[0];
		s2[aai] = new Array();v2[aai] = new Array();
		if(v1[aai]==dv1){s1i = aai;}
		bbbb=aaa[1];
		if(dt2!=""&&!selectonce){if(bbbb==""){bbbb=dt2;}else{bbbb=dt2+_s.charAt(2)+bbbb;}}
		bb=bbbb.split(_s.charAt(2));
		for(bbi=0;bbi< bb.length;bbi++){
			tmps2 = bb[bbi].split(_s.charAt(3));
			s2[aai][bbi] = tmps2[0];v2[aai][bbi] = (tmps2.length==2)?tmps2[1]:tmps2[0];
			if(v2[aai][bbi]==dv2){s2i = bbi;}
		}
	}
	for(var i=0;i<o1.options.length;i++){o1.remove(i);i--;}
	for(k=0;k<s1.length;k++){o1.options.add(new Option(s1[k],v1[k]));}
	o1.selectedIndex=s1i;
	for(var i=0;i<o2.options.length;i++){o2.remove(i);i--;}
	for(k=0;k<s2[s1i].length;k++){o2.options.add(new Option(s2[s1i][k],v2[s1i][k]));}
	o2.selectedIndex=s2i;
}
function HwTwoSelect(o1,o2,liststr,dt1,dt2,t){this.o1=o1;this.o2=o2;this.str=liststr;this.dt1=dt1;this.dt2=dt2;this.selectonce=t}
//-->
</SCRIPT>
<form method="post" name=myform>
选择一次：<select name="a" onchange="TwoSelectInit(test1,this.value)"></select>　<select name="b"></select><hr>
选择两次：<select name="aa" onchange="TwoSelectInit(test2,this.value)"></select>　<select name="bb"></select><hr>
有初始值：<select name="aaa" onchange="TwoSelectInit(test3,this.value)"></select>　<select name="bbb"></select>

</form>
<SCRIPT LANGUAGE="JavaScript">
<!--
var selecttext=""
+"搜索@search|Google@http://www.google.com/^Yahoo@http://www.yahoo.com/"
+"*收藏@fav|无忧视窗@http://www.51windows.Net/^蓝色理想@http://www.blueidea.com/^POPO@http://plod.popoever.net/"
+"";
var test1 = new HwTwoSelect(document.myform.a,document.myform.b,selecttext,"－分类－@","－网址－@",1);//最后的参数表示，选了一级菜单后，二级菜单是否还要显示“请选择”，1或true代码，不显示，0或false代表显示
TwoSelectInit(test1);

var test2 = new HwTwoSelect(document.myform.aa,document.myform.bb,selecttext,"－分类－@","－网址－@",0);
TwoSelectInit(test2);

var test3 = new HwTwoSelect(document.myform.aaa,document.myform.bbb,selecttext,"－分类－@","－网址－@",0);
TwoSelectInit(test3,"fav","http://www.51windows.Net/");
//-->
</SCRIPT>
<p>以下是示例代码，详细请查看源文件：<hr>
<p>&lt;form method="post" name=<font color="#FF00FF">myform</font>&gt;<br>
&lt;select name=&quot;<font color="#FF0000">select1</font>&quot; onchange=&quot;TwoSelectInit(<font color="#0000FF">ttt</font>,this.value)&quot;&gt;&lt;/select>　&lt;select  
name=&quot;<font color="#FF0000">select2</font>&quot;&gt;&lt;/select>&lt;hr><br>
&lt;/form></p>
<p>&lt;SCRIPT LANGUAGE="JavaScript"><br>  
&lt;!--<br>
var <font color="#008000">selecttext</font>=&quot;&quot;<br> 
+"搜索@search|Google@http://www.google.com/^Yahoo@http://www.yahoo.com/"<br>
+"*收藏@fav|无忧视窗@http://www.51windows.Net/^蓝色理想@http://www.blueidea.com/^POPO@http://plod.popoever.net/"<br>
+"";<br>
<br>
var <font color="#0000FF">ttt</font> = new HwTwoSelect(document.<font color="#FF00FF">myform</font>.<font color="#FF0000">select1</font>,document.<font color="#FF00FF">myform</font>.<font color="#FF0000">select2</font>,<font color="#008000">selecttext</font>,&quot;－分类－@","－网址－@",1);<br>
TwoSelectInit(<font color="#0000FF">ttt</font> ,&quot;fav&quot;,&quot;http://www.51windows.Net/&quot;);<br> 
<br>
//--><br>
&lt;/SCRIPT></p>
<p><font color="#FF0000">bug:在二级菜单有初始值时，如果表单重置，二级菜单的值会变为空</font></p>
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