Asynchronous Programming di JavaScript

async01.js

// Aku akan menyelesaikannya nanti!
// Fungsi yang berjalan paralel dengan fungsi lain disebut asinkron

// set time out
setTimeout(() => {
  document.getElementById("demo").innerHTML = "Urutan 1";
}, 3000);

setTimeout(() => {
  document.getElementById("demo").innerHTML = "Urutan 2";
}, 5000);

document.getElementById("demo").innerHTML = "Urutan 3"

async02.js

// set interval
let interval01 = 0;
let interval02 = 0;

let task1 = setInterval(() => {
  document.getElementById("demo1").innerHTML = `Task 1: ${interval01++}`;
}, 3000);

let task2 = setInterval(() => {
  document.getElementById("demo2").innerHTML = `Task 2: ${interval02++}`;
}, 5000);

document.getElementById("demo1").addEventListener("click", () => {
  clearInterval(task1);
})

document.getElementById("demo2").addEventListener("click", () => {
  clearInterval(task2);
})

async03.js

setInterval(myFunction, 1000);

function myFunction() {
  let d = new Date();
  document.getElementById("demo").innerHTML=
  d.getHours() + ":" +
  d.getMinutes() + ":" +
  d.getSeconds();
}

async04.js

// i will promise to send result
let sales = {
  harga: 20000,
  dibayar: 20000,
  selesai: false,
  status: "none"
}

let promise = new Promise(function(resolve, reject) {
  setTimeout(() => {
  	if (sales.harga <= sales.dibayar) {
      sales.selesai = true;
      sales.status = "success";
      resolve(sales);
    } else {
      sales.status = "fail";
      reject(sales);
    }
  }, 5000)
});

// not work, this is sequence control
if (sales.status === "success") {
  alert("success");
} else if (sales.status === "fail") {
  alert("fail");
}

// work, this is style of promise (async)
promise.then((value) => {
  alert(value.status);
}).catch((error) => {
  alert(error.status);
});

alert("running program");

async05.js

// using await for program promise (async) like control sequence in function
let promise = new Promise((resolve, reject) => {
  let sales = {
    harga: 20000,
    dibayar: 20000,
    selesai: false,
    status: "none"
  };
  
  setTimeout(() => {
  	if (sales.harga <= sales.dibayar) {
      sales.selesai = true;
      sales.status = "success";
      resolve(sales);
    } else {
      sales.status = "fail";
      reject(sales);
    }
  }, 5000)
});


async function main() {
 let result = await promise;
 alert(result.status);
}

main();
alert("running now")