路由页面错误代码时出错：错误：ENOENT，stat'/public/index.html'使用节点

I use This code :

我用这段代码:

var express = require("express");
var path =  require("path");
var app =  express();
app.use(express.static(path.join(__dirname, 'public')));
app.use("/",function(req,res){
    res.sendfile('/public/index.html');
  //res.send("test");
}),
app.listen(5401)
var express = req