1.后端代码
var dp = 456;
var back = 'callback(\{\dp\ : \ ' + dp + '\ }\)';
res.send(back);
2.前端代码
<script type="text/javascript">
function callback(data){
console.log(data);
} </script>
<script type="text/javascript" src="http://127.0.0.1:3000/jsonp"></script>