本文介绍给下拉框和输入框赋值，代码如下：
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>select</title>
</head>
<body>
<label class="w3-label">请求领域</label>
<select class="w3-select" name="Field" id="fieldname">
<option value="" disabled selected>选择请求领域型</option>
<option value="武侠">武侠</option>
<option value="科技">科技</option>
<option value="医疗">医疗</option>
<option value="计算机">计算机</option>
<option value="军事">军事</option>
<option value="容器">容器</option>
</select>
<label class="w3-label">详细描述</label>
<input class="w3-input" name="Description" id="desc">
<script>
var field = "容器"
var select2 = document.getElementById('fieldname');
for (var i = 0, count = select2.options.length; i < count; i++) {
if (select2.options[i].text == field) {
select2.selectedIndex = i;
break;
}
}
var desc = "星期五"
document.getElementById("desc").value = desc;
</script>
</body>
</html>