promise.all() example

https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Promise/all



var promise1 = Promise.resolve(3);
var promise2 = 42;
var promise3 = new Promise(function(resolve, reject) {
  setTimeout(resolve, 100, 'foo');
});

var promise4 = Promise.resolve(3);
var promise5 = 55;
var promise6 = new Promise(function(resolve, reject) {
  setTimeout(resolve, 10000, 'foo');
});

Promise.all([promise1, promise2, promise3]).then((data)=> {
  return call();
}).then((data)=> {
console.log("---",data);
});

function call(){
return Promise.all([promise4, promise5, promise6]);
}

=========================================

var promise1 = Promise.resolve(3);

var promise2 = 42;

var promise3 = new Promise(function(resolve, reject) {

setTimeout(resolve, 100, 'foo');

});

var promise4 = Promise.resolve(3);

var promise5 = 55;

var promise6 = new Promise(function(resolve, reject) {

setTimeout(resolve, 10000, 'foo');

});

Promise.all([promise1, promise2, promise3]).then((data)=> {

let a= call();

console.log('---a',a);

return a;

}).then((data)=> {

console.log("---b",data);

});

function call(){

return Promise.all([promise4, promise5, promise6]).then((data1)=>{

console.log('data1',data1);

return data1[0];

})

}
====================================how promis.all() work=========

var promise1 = Promise.resolve(3);

var promise2 = 42;

var promise3 = new Promise(function(resolve, reject) {

setTimeout(resolve, 100, 'foo');

});

var promise4 = Promise.resolve(3);

var promise5 = Promise.resolve(55);

var promise6 = new Promise(function(resolve, reject) {

setTimeout(resolve, 10000, 'pawan');

});

var promise7 = new Promise(function(resolve, reject) {

setTimeout(resolve, 1000, 'foo');

});

Promise.all([promise1, promise2, promise3]).then((data)=> {

let abc=call();

console.log('--abc---',abc);

return call();

}).then((data)=> {

console.log("---123",data);

});

function call(){

return Promise.all([promise5,promise6,promise4,promise7]).then((res)=>{

return datasend = res;

});

}

// expected output: Array [3, 42, "foo"]

if you want to get promise all result in expected order then all the promise function and store that promise in a variable and pass that variable in promise all([a,b,c])in order you want.

=============note if don't want to preserve promise resolve order then you can call your promise inside promise.all([]) ;====================

var promise1 = Promise.resolve(3);

var promise2 = 42;

var promise3 = new Promise(function(resolve, reject) {

setTimeout(resolve, 100, 'foo');

});

Promise.all([promise1, promise2, promise3]).then((data)=> {

let abc=call();

console.log('--abc---',abc);

return call();

}).then((data)=> {

console.log("---123",data);

});

function call(){

return Promise.all([

Promise.resolve(3),

Promise.resolve(55), new Promise(function(resolve, reject) {

setTimeout(resolve, 10000, 'pawan');

}),

new Promise(function(resolve, reject) {

setTimeout(resolve, 1000, 'foo');

})

]).then((res)=>{

return datasend = res;

});

}

// expected output: Array [3, 42, "foo"]