select object

select object

A <select> tag corresponds to a select object.

select object properties

options[]: Set or return the <option> tag in the drop-down list array.
selectedIndex: Set or select the index number of the specified <option>.
length: Specify the number of <option> tags in the drop-down list.
name: element name.

option object

An <option> tag corresponds to an option object.

option object attribute

text: refers to the text between <option> and </option> .
value: refers to the attribute of the <option> tag.

<!DOCTYPE HTML>
<html>
<head>
    <meta charset="utf-8" />
    <title>php.cn</title>
    <script>
        window.onload=function(){
            var Form = document.form;
            Form.city.options[2].text = "合肥";
            alert(Form.city.options[2].text);
        }
    </script>
</head>
<body>
    <form name="form" method="post" action="">
        城市：
        <select name="city">
            <option value="0">北京</option>
            <option value="1">上海</option>
            <option value="2">深圳</option>
        </select>
    </form>
</body>
</html>

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<!DOCTYPE HTML>
<html>
<head>
 <meta charset="utf-8" />
 <title>php.cn</title>
 <script>
 window.onload=function(){
 var Form = document.form;
 Form.city.options[2].text = "合肥";
 alert(Form.city.options[2].text);
 }
 </script>
</head>
<body>
 <form name="form" method="post" action="">
 城市：
 <select name="city">
 <option value="0">北京</option>
 <option value="1">上海</option>
 <option value="2">深圳</option>
 </select>
 </form>
</body>
</html>
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