<form name="form1" method="post" action="">
<select name="select" onchange="this.form.textfield.value=value">
<option selected>请选择</option>
<option value="red">红色</option>
<option value="green">绿色</option>
<option value="blue">蓝色</option>
</select>
<br>
您选择的颜色是:
<input type="text" name="textfield">
</form>
<select name="select" onchange="this.form.textfield.value=value">
<option selected>请选择</option>
<option value="red">红色</option>
<option value="green">绿色</option>
<option value="blue">蓝色</option>
</select>
<br>
您选择的颜色是:
<input type="text" name="textfield">
</form>
<form name="form1" method="post" action="">
<select name="select" onchange="this.form.textfield.value=this[this.selectedIndex].value">
<option selected>请选择</option>
<option value="red">红色</option>
<option value="green">绿色</option>
<option value="blue">蓝色</option>
</select>
<br>
您选择的颜色是:
<input type="text" name="textfield">
</form>