效果
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代码
<!DOCTYPE html>
<html>
<head>
<title>web4</title>
</head>
<body>
<fieldset>
<legend>跳转</legend>
<span>请选择要跳转的网址:</span><br><br>
<from onchange="peal()">
<table>
<tr>
<td>
<select id="website">
<option value="" selected></option>
<option name="website1" value="www.baidu.com">百度</option>
<option name="website2" value="www.163.com">网易</option>
<option name="website3" value="www.qq.com">腾讯</option>
</select>
</td>
<td>
<input type="text" name="websiteText" id="websiteText">
</td>
<td>
<button value="跳转" onclick="jump()">跳转</button>
</td>
</tr>
</table>
</from>
</fieldset>
</body>
<script type="text/javascript"> var website; function peal(){ website = document.getElementById("website").value; document.getElementById("websiteText").value= website; } function jump(){ if(website==null){ alert("请选择要跳转的网址"); }else{ window.open("http://"+website); } } </script>
</html>