js 操作select和option

穆乙發表於2013-09-27

1.動態建立select

     function createSelect(){

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

2.新增選項option

     function addOption(){

          //根據id查詢物件,
           var obj=document.getElementByIdx_x('mySelect');

           //新增一個選項
obj.add(new Option("文字","值"));    //這個只能在IE中有效
         obj.options.add(new Option("text","value")); //這個相容IE與firefox
     }

3.刪除所有選項option

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

     }

4.刪除一個選項option

function removeOne(){
           var obj=document.getElementByIdx_x('mySelect');

           //index,要刪除選項的序號,這裡取當前選中選項的序號

var index=obj.selectedIndex;
obj.options.remove(index);
     }

5.獲得選項option的值

var obj=document.getElementByIdx_x('mySelect');

var index=obj.selectedIndex; //序號,取當前選中選項的序號

var val = obj.options[index].value;

6.獲得選項option的文字

var obj=document.getElementByIdx_x('mySelect');

var index=obj.selectedIndex; //序號,取當前選中選項的序號

var val = obj.options[index].text;

7.修改選項option

var obj=document.getElementByIdx_x('mySelect');

var index=obj.selectedIndex; //序號,取當前選中選項的序號

var val = obj.options[index]=new Option("新文字","新值");

8.刪除select

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

 

整個例項的完整程式碼如下:

<!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 $(id)
    {
     return document.getElementByIdx_x(id)
    }
    function show()
    {
     var selectObj=$("area")
     var myOption=document.createElement_x("option")
     myOption.setAttribute("value","10")
     myOption.appendChild(document.createTextNode("上海"))
     var myOption1=document.createElement_x("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_x("select")
      sh.add(new Option("浦東新區","101"))
      sh.add(new Option("黃浦區","102"))
      sh.add(new Option("徐彙區","103"))
      sh.add(new Option("普陀區","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_x("select")
      nj.add(new Option("玄武區","201"))
      nj.add(new Option("白下區","202"))
      nj.add(new Option("下關區","203"))
      nj.add(new Option("棲霞區","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="顯示" onclick="show()">
<input type=button value="計算結點" onclick="calc()">
<input type=button value="刪除" onclick="remove()">
</body>
</html>

 

改進版:在select中新增、修改、刪除option元素

function watch_ini(){ // 初始
for(var i=0; i<arguments.length; i++){
var word = document.createElement_x("OPTION");
word.text = arguments[i];
watch.keywords.add(word); // watch. is form name
}
}
function watch_add(f){ // 增加
var word = document.createElement_x("OPTION");
word.text = f.word.value;
f.keywords.add(word); 
}
但上述 add() 方法只在IE下有效,為相容FF和Opera,對上述程式碼進行了一下改進,改動後程式碼如下: function watch_ini(){ // 初始
for(var i=0; i<arguments.length; i++){
   var oOption=new Option(arguments[i],arguments[i]);
   document.getElementByIdx_x("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;
}


整個例項的完整程式碼如下:

<!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.getElementByIdx_x("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){ // 編輯
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){ // 刪除
f.keywords.remove(f.keywords.selectedIndex);
}
function watch_set(f){ // 儲存
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","爾"); // 初始關鍵詞
//-->
</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="刪除" onclick="watch_del(this.form);" />
<input type="button" value="儲存" onclick="watch_set(this.form);" />
</form>

用一個字串建立一個陣列方法:

<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

      今天除錯了一段js,在ie上執行良好,在火狐上除錯出現錯誤,查資料發現

      obj.add(new Option("文字","值"));    //這個只能在IE中有效
               obj.options.add(new Option("text","value")); //這個相容IE與firefox

      因為這段程式碼,在網上查資料收藏了這篇文章,實時的溫故js

      共勉!!

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