function oo(){
document.getElementsByName("txt")[0].value=document.getElementsByName("selectname")[0].value}
name 不要用select这样的东西
document.getElementsByName("txt")[0].value=document.getElementsByName("selectname")[0].value}
name 不要用select这样的东西
调试欢乐多
var obj = document.getElementsByName("select");
txt.value= obj.options[obj.selectedIndex].value;
}
<select size=1 name="selectname">
<option></option>
<option>ok</option>
<option>no</option>
</select>
<input type=text name="txt">
<input type=submit value=yes onclick=oo()>
<script>
function oo(){
document.getElementsByName("txt")[0].value=document.getElementsByName("selectname")[0].value
}
</script><!--按照2楼的意见修改如下,运行显示options为空或不是对象-->
<select size=1 name="select">
<option></option>
<option>ok</option>
<option>no</option>
</select>
<input type=text name="txt">
<input type=submit value=yes onclick=oo()>
<script>
function oo(){
var obj = document.getElementsByName("select");
txt.value= obj.options[obj.selectedIndex].value;
}
</script>
<html>
<head>
<title>select</title>
<script>
function oo(){
var obj = document.getElementById("select");
var txt = document.getElementById("txt");
txt.value= obj.value;
}
</script>
</head>
<body>
<select name="select" id="select">
<option value="null"> </option>
<option value="ok"> ok </option>
<option value="no"> no </option>
</select>
<input type="text" name="txt" id="txt">
<input type="button" value="yes" onclick="oo()">
</body>
</html>
<select size=1 name="selectname">
<option></option>
<option value="ok">ok</option>
<option value="no">no</option>
</select>
<input type=text name="txt">
<input type=submit value=yes onclick=oo()>
<script>
function oo(){
txt.value=selectname.value;
}
</script>