javascript - how does this callback function work -


i new nodejs , n00b of javascript. saw code create server using nodejs. can understand anonymous function called after request reached server.

var http=require("http"); http.createserver(function(request,response){  response.writehead(200,{"content-type":"text/plain"});  response.write("hello world");  responde.end(); }).listen(8888);

my question how implement similar createserver function (foo() bar())..in order understand how method works.

in order make clear. have done not working. , how make work createserver() ?

function dummycallback(para1,para2,callback) {  console.log('para1 ' + para1+' para2 '+ para2);  callback(); }  dummycallback(1,2,function(req,res) {  req.senddata("good"); });

i have seen these code everywhere in nodejs desperately want know details...thanks again

maybe, asking how anonymous function works.

var fun = function(foo){     if (foo) foo(1, 2); ///< if function foo exists, call it. } fun(function(p1, p2){     return p1 + p2; });

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