• js 操作select和option(转载)


    1.动态创建select

    function createSelect(){

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

    2.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
    }

    3.删除所有选项option

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

    }

    4.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);
    }

    5.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;

    6.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;

    7.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");

    8.删除select

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

    整个实例的完整代码如下:

    <!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);
    }
    但上述 add() 方法只在IE下有效,为兼容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>

    用一个字符串创建一个数组方法:

    <script language="javascript">

    1. </body>
      </html>
    2. <script>
    3. function spli(){
    4. datastr="2,2,3,5,6,6";
    5. var str= new Array();
    6. str=datastr.split(",");
    7. for (i=0;i<str.length ;i++ )
    8. { document.write(str[i]+"<br/>"); }
    9. }
    10. spli();
    11. </script
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  • 原文地址:https://www.cnblogs.com/holygis/p/2171576.html
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