JS动态添加option和删除option

来源：互联网发布：希区柯克剧场知乎编辑：程序博客网时间：2024/05/01 00:03

本文转载自http://www.jb51.net/article/35205.htm
仅供学习之用，留着随时查看

动态创建select

function createSelect(){ var mySelect = document.createElement("select"); mySelect.id = "mySelect"; document.body.appendChild(mySelect); }

添加选项option

function addOption(){ //根据id查找对象， var obj=document.getElementById('mySelect'); //添加一个选项 obj.add(new Option("文本","值")); //这个只能在IE中有效 obj.options.add(new Option("text","value")); //这个兼容IE与firefox }

删除所有选项option

function removeAll(){ var obj=document.getElementById('mySelect'); obj.options.length=0; }

删除一个选项option

function removeOne(){ var obj=document.getElementById('mySelect'); //index,要删除选项的序号，这里取当前选中选项的序号 var index=obj.selectedIndex; obj.options.remove(index); }

获得选项option的值

var obj=document.getElementById('mySelect'); var index=obj.selectedIndex; //序号，取当前选中选项的序号 var val = obj.options[index].value;

　获得选项option的文本

var obj=document.getElementById('mySelect'); var index=obj.selectedIndex; //序号，取当前选中选项的序号 var val = obj.options[index].text;

　修改选项option

var obj=document.getElementById('mySelect'); var index=obj.selectedIndex; //序号，取当前选中选项的序号 var val = obj.options[index]=new Option("新文本","新值");

　删除select

function removeSelect(){ var mySelect = document.getElementById("mySelect"); mySelect.parentNode.removeChild(mySelect); }

　完整代码如下

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//ZH-CN" "http://www.w3.org/TR/html4/strict.dtd"> <html> <head> <meta http-equiv="Content-Type" content="text/html"> <head> <script language=JavaScript> function $(id) { return document.getElementById(id) } function show() { var selectObj=$("area") var myOption=document.createElement("option") myOption.setAttribute("value","10") myOption.appendChild(document.createTextNode("上海")) var myOption1=document.createElement("option") myOption1.setAttribute("value","100") myOption1.appendChild(document.createTextNode("南京")) selectObj.appendChild(myOption) selectObj.appendChild(myOption1) } function choice() { var index=$("area").selectedIndex; var val=$("area").options[index].getAttribute("value") if(val==10) { var i=$("context").childNodes.length-1; var remobj=$("context").childNodes[i]; remobj.removeNode(true) var sh=document.createElement("select") sh.add(new Option("浦东新区","101")) sh.add(new Option("黄浦区","102")) sh.add(new Option("徐汇区","103")) sh.add(new Option("普陀区","104")) $("context").appendChild(sh) } if(val==100) { var i=$("context").childNodes.length-1; var remobj=$("context").childNodes[i]; remobj.removeNode(true) var nj=document.createElement("select") nj.add(new Option("玄武区","201")) nj.add(new Option("白下区","202")) nj.add(new Option("下关区","203")) nj.add(new Option("栖霞区","204")) $("context").appendChild(nj) } } function calc() { var x=$("context").childNodes.length-1; alert(x) } function remove() { var i=$("context").childNodes.length-1; var remobj=$("context").childNodes[i]; remobj.removeNode(true) } </script> <body> <div id="context"> <select id="area" onchange="choice()"> </select> </div> <input type=button value="显示" onclick="show()"> <input type=button value="计算结点" onclick="calc()"> <input type=button value="删除" onclick="remove()"> </body> </html>

　改进版：在select中添加、修改、删除option元素

function watch_ini(){ // 初始 for(var i=0; i<arguments.length; i++){ var word = document.createElement("OPTION"); word.text = arguments[i]; watch.keywords.add(word); // watch. is form name } } function watch_add(f){ // 增加 var word = document.createElement("OPTION"); word.text = f.word.value; f.keywords.add(word); }

　兼容FF和Opera，对上述代码进行了一下改进，改动后代码如下：

function watch_ini(){ // 初始 for(var i=0; i<arguments.length; i++){ var oOption=new Option(arguments[i],arguments[i]); document.getElementById("MySelect")[i]=oOption; } } function watch_add(f){ // 增加 var oOption=new Option(f.word.value,f.word.value); f.keywords[f.keywords.length]=oOption; }

　整个实例的完整代码如下

<!doctype html public "-//w3c//dtd html 4.0 transitional//en"> <html> <head> <title>javascript select options text value</title> <meta name="keywords" content="javascript select options text value add modify delete set"> <meta name="description" content="javascript select options text value add modify delete set"> <script language="javascript"> <!-- function watch_ini(){ // 初始 for(var i=0; i<arguments.length; i++){ var oOption=new Option(arguments[i],arguments[i]); document.getElementById("MySelect")[i]=oOption; } } function watch_add(f){ // 增加 var oOption=new Option(f.word.value,f.word.value); f.keywords[f.keywords.length]=oOption; } function watch_sel(f){ // 编辑 f.word.value = f.keywords[f.keywords.selectedIndex].text; } function watch_mod(f){ // 修改 f.keywords[f.keywords.selectedIndex].text = f.word.value; } function watch_del(f){ // 删除 f.keywords.remove(f.keywords.selectedIndex); } function watch_set(f){ // 保存 var set = ""; for(var i=0; i<f.keywords.length; i++){ set += f.keywords[i].text + ";"; } confirm(set); } //--> </script> </head> <body> <form name="watch" method="post" action=""> <select id="MySelect" name="keywords" size="10" onchange="watch_sel(this.form)"></select><br> <script language="javascript"> <!-- watch_ini("我","你","妳","他","她","它","尔"); // 初始关键词 //--> </script> <input type="text" name="word" /><br /> <input type="button" value="增加" onclick="watch_add(this.form);" /> <input type="button" value="修改" onclick="watch_mod(this.form);" /> <input type="button" value="删除" onclick="watch_del(this.form);" /> <input type="button" value="保存" onclick="watch_set(this.form);" /> </form>

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