Promises

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Resources

Javascript Promises

Exercises

1. Create a form with 2 fields a user name and a email. Create a function (with promises) to validate the form and submit the form if it is correct.
2. Make a web page with a button (button text: Load image), when we click on that button you have use "promises" to load an image from your server and catch the errors, if there are
3. With the given code, create a web page that call a server with some data (it's doesn't matter what data) and print the data on the page applying some kind of format.

   const loadJSON = (file) => {
     return new Promise((resolve, reject) => {
       const xhr = new XMLHttpRequest();
       xhr.open('GET', file, true);
       xhr.responseType = 'json';
       xhr.onload = () => {
         if (xhr.status === 200) {
           resolve(xhr.response);
         } else {
           reject(xhr.statusText);
         }
       };
       xhr.onerror = () => reject(xhr.statusText);
       xhr.send();
     });
   };
   
   

4. Using the given code and this api ( https://restcountries.com/ ), create a web application that asks user to enter a capital form some country and displays the name of the country and its flag

   const findData = async () => {
     const res = await fetch("API URL"); 
     const country = await res.json(); 
   };
   
   findData();
   
   findData = new Promise(function (myResolve,myReject) {
     
     res = fetch("API URL")
     if(res){
       myResolve(res)
     }
   });
   
   findData.then(
     function (value) {
       //console.log(value.json())
       return value.json()
     }
     ).then(res =>{
       console.log(res[0].name.common)
     });
   

5. Modify the previous exercise to display in addition to the name of the country and its flag, the name and flag of the neighboring countries. Hint: Promises.all()