new promise in js code example
Example 1: javascript promise
var promise = new Promise(function(resolve, reject) {
// do some long running async thing…
if (/* everything turned out fine */) {
resolve("Stuff worked!");
}
else {
reject(Error("It broke"));
}
});
//usage
promise.then(
function(result) { /* handle a successful result */ },
function(error) { /* handle an error */ }
);
Example 2: making promises in js
getData()
.then(data => console.log(data))
.catch(error => console.log(error));
Example 3: javascript promises
var posts = [
{name:"Mark42",message:"Nice to meet you"},
{name:"Veronica",message:"I'm everywhere"}
];
function Create_Post(){
setTimeout(() => {
posts.forEach((item) => {
console.log(`${item.name} --- ${item.message}`);
});
},1000);
}
function New_Post(add_new_data){
return new Promise((resolve, reject) => {
setTimeout(() => {
posts.push(add_new_data);
var error = false;
if(error){
reject("Something wrong in </>, Try setting me TRUE and check in console");
}
else{
resolve();
}
},2000);
})
}
New_Post({name:"War Machine",message:"I'm here to protect"})
.then(Create_Post)
.catch(err => console.log(err));