app.use middleware code example

Example 1: middleware uses

const methodOverride = require('method-override');
const { url } = require("inspector");
server.use(methodOverride('_method'));


// middleware
server.use(express.static("./public"));
server.set("view engine", "ejs");
server.use(express.urlencoded({ extended: true }));

Example 2: what is app.use() used for

//app.get will see only exact match ex.> "/book" here app.get will not allow /book/1, etc 
//but app.use is different see below

//what is difference between app.use and app.all
//app.use takes only 1 callback while app.all takes multiple callbacks
//app.use will only see whether url starts with specified path But, app.all() will match the complete path

app.use( "/book" , middleware);
// will match /book
// will match /book/author
// will match /book/subject

app.all( "/book" , handler);
// will match /book
// won't match /book/author   
// won't match /book/subject    

app.all( "/book/*" , handler);
// won't match /book        
// will match /book/author
// will match /book/subject

Example 3: middleware uses

server.use(express.static('./public'));
server.use(express.json());
server.use(express.urlencoded({extended: true}));
const methodOverride = require('method-override');
server.use(methodOverride('_method'));
server.set('view engine', 'ejs');