直接上代码
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width,initial-scale=1.0">
<title>demo</title>
</head>
<body>
<div id="app">
姓名：<input type="text" name="name" id="name" value=""
class="form-control form-control-sm"><br/>
手机号：<input type="tel" name="tel" id="tel" value="123456789"
class="form-control form-control-sm" readonly><br/>
所属项目:<select name="projectId" id="projectId" >
<option value="">请选择项目</option>
<option value="1">项目一</option>
<option value="2">项目二</option>
<option value="3">项目三</option>
</select><br/>
自动加载：<input type="text" id="title" name="title">
</div>
</body>
<script src="jquery.min.js"></script>
<script type="text/javascript">
function setTitle(){
var name = $("#name").val();
var project = $('#projectId option:selected').text();
var telValue = $("#tel").val();
$("#title").val(name + "-" + project + "-" + telValue);
}
setTitle();
$("#name").change(function () {
setTitle();
});
$("#projectId").change(function () {
setTitle();
});
</script>
</html>
