select框互操作

2024-02-04 20:18

文章标签 select 互操作

本文主要是介绍select框互操作，希望对大家解决编程问题提供一定的参考价值，需要的开发者们随着小编来一起学习吧！

主要是两个select在onChange时的两个方法，

删除一个select框中的项

document.all("test").options.remove(i)

增加一个select框中的项

document.all("test").options.add(new Option("选项","值"));

selectedIndex表示该选框当前选的值的序号，从0~length-1表示,可以指定selectedIndex的值，既可指定其对应的选项.

源程序

<HTML>
<HEAD>
<TITLE> New Document </TITLE>
<META NAME="Generator" CONTENT="EditPlus">
<META NAME="Author" CONTENT="">
<META NAME="Keywords" CONTENT="">
<META NAME="Description" CONTENT="">
<style type="text/css">
body{font-family:Courier New, Courier}
select{font-size:8pt;font-family:Courier New, Courier}
input{font-size:8pt;font-family:Courier New, Courier}
</style>
<SCRIPT LANGUAGE="JavaScript">
<!--
var Name=new Array(3);
var Value=new Array(3);
Name[1]=new Array("Zosatapo1","Zosatapo2","Zosatapo3","Zosatapo4");
Name[2]=new Array("Reic Yang1","Reic Yang2","Reic Yang3","Reic Yang4");

function change()
{
selIndex=document.all("test").selectedIndex;
if(document.all("test").selectedIndex==0)
return;

for(i=document.all("test").options.length-1;i>-1;i--)
{
document.all("test").options.remove(i);
}

for(i=0;i<Name[selIndex].length;i++)
{
document.all("test").options.add(new Option(Name[selIndex][i],"name"+i));
}

}

function changeEx(){

for(i=document.all("sub").options.length;i>0;i--)
{
document.all("sub").options.remove(i-1);
}

if(document.all("main").selectedIndex==0){
document.all("sub").options.add(new Option("==========","-1"));
return;}

selIndex=document.all("main").selectedIndex;

for(i=0;i<Name[selIndex].length;i++)
{
document.all("sub").options.add(new Option(Name[selIndex][i],"name"+i));
}

}

function reset(){
for(i=document.all("test").options.length-1;i>-1;i--)
{
document.all("test").options.remove(i);
}

document.all("test").options.add(new Option("==========","-1"));

document.all("test").options.add(new Option("Zosatapo","1"));

document.all("test").options.add(new Option("Reic Yang","2"));

}

function display(object){
alert(object.options[object.selectedIndex].text+" "+object.options[object.selectedIndex].value);
}
//-->
</SCRIPT>
</HEAD>

<BODY BGCOLOR="#FFFFFF">
First Sample:<br><font color="blue">All items will change After you Selected!</font><br>
<SELECT id="test" οnchange="change();">
<option value="-1" selected>==========
<option value="1">Zosatapo
<option value="2">Reic Yang
</SELECT><input name="Reset Select" type="button" value="Reset Select" οnclick="reset();" ><br><br>

Second Sample:<br><font color="blue">You selected Item in Main Select will change the Sub select Content!</font><br>
Main Select:<SELECT id="main" οnchange="changeEx();">
<option value="-1" selected>==========
<option value="1">Zosatapo
<option value="2">Reic Yang
</SELECT>

Sub Select:<SELECT id="sub" οnchange="display(this);">
<option value="-1" selected>==========
</SELECT><br><br>
</BODY>
</HTML>

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