Alfie Mellor

Alfie Mellor

1593230166

How to Use Fetch to Make AJAX Calls in JavaScript

I will be sharing bite sized learnings about JavaScript regularly in this series. We’ll cover JS fundamentals, browsers, DOM, system design, domain architecture and frameworks.

Fetch is an interface for making an AJAX request in JavaScript. It is implemented widely by modern browsers and is used to call an API.

const promise = fetch(url, [options])

Calling fetch returns a promise, with a Response object. The promise is rejected if there is a network error, and it’s resolved if there is no problem connecting to the server and the server responded a status code. This status code could be 200s, 400s or 500s.

A sample FETCH request -

fetch(url)
.then(response => response.json())
.catch(err => console.log(err))

The request is sent as a GET by default. To send a POST / PATCH / DELETE / PUT you can use the method property as part of options parameter. Some other possible values options can take -

  • method: such as GET, POST, PATCH
  • headers: Headers object
  • mode: such as cors, no-cors, same-origin
  • cache: cache mode for request
  • credentials
  • body

#javascript #ajax #api #developer

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Buddha Community

How to Use Fetch to Make AJAX Calls in JavaScript

Making AJAX Calls using the Fetch API

In this post we’ll do everything we did in the second post, but with Fetch API.

What’s this Fetch API?

The almighty docs say

The Fetch API provides an interface for fetching resources (including across the network). It will seem familiar to anyone who has used XMLHttpRequest but the new API provides a more powerful and flexible feature set.

I prepared this demo page so that you can test.

You’ll remember from the last post that in order to make an AJAX call with jQuery, you have to do something like this:

$('#result').load('http://nikola-breznjak.com/_testings/ajax/test1.php?ime=Nikola');

Go ahead and run that code on the demo page in the browser’s dev tools Console

Now, the very same thing with the Fetch API looks like this:

var link = 'http://nikola-breznjak.com/_testings/ajax/test2.php';
fetch(link)
    .then(function(response){
        return response.json()
    })
    .then(function(result){
        var oglasiHTML = '';
        $.each(result, function(index, oglas){
            var klasaCijene = '';
            if (oglas.cijena < 100){
                klasaCijene = 'is-success';
            }
            else if (oglas.cijena >= 100 && oglas.cijena < 300){
                klasaCijene = 'is-info';
            }
            else if (oglas.cijena >= 300){
                klasaCijene = 'is-danger';
            }
 
            oglasiHTML += `
                <div class="columns">
                    <div class="column is-one-quarter">
                        <span class="tag ${klasaCijene}">${oglas.cijena}</span>
                    </div>
                    <div class="column">${oglas.tekst}</div>
                </div>
            `;
        });
 
        $('#oglasi').html(oglasiHTML);
    });

Go ahead and try it in the Console. Change the ime parameter, and you’ll see that the text on the page will change to Hello [name], where [name] will be the parameter you entered. Note that in the example above I still used jQuery to set the content of the div with id result.

The docs have way more info on this but, as they say, the difference between fetch() and $.ajax() is in two main things:

  • The Promise returned from fetch() won’t reject on HTTP error status even if the response is an HTTP 404 or 500. Instead, it will resolve normally (with ok status set to false), and it will only reject on network failure or if anything prevented the request from completing.
  • By default, fetch() won’t send or receive any cookies from the server, resulting in unauthenticated requests if the site relies on maintaining a user session (to send cookies, the credentials init option must be set).

⚠️ At a later point you may want to read a bit more about Promises in Javascript.

Rewriting the mini project

I encourage you to try it for yourself and then check your solution to mine.

The mini project (which you can test here) would be rewritten like this:

var link = 'http://nikola-breznjak.com/_testings/ajax/test2.php';
fetch(link)
    .then(function(response){
        return response.json()
    })
    .then(function(result){
        var oglasiHTML = '';
        $.each(result, function(index, oglas){
            var klasaCijene = '';
            if (oglas.cijena < 100){
                klasaCijene = 'is-success';
            }
            else if (oglas.cijena >= 100 && oglas.cijena < 300){
                klasaCijene = 'is-info';
            }
            else if (oglas.cijena >= 300){
                klasaCijene = 'is-danger';
            }
 
            oglasiHTML += `
                <div class="columns">
                    <div class="column is-one-quarter">
                        <span class="tag ${klasaCijene}">${oglas.cijena}</span>
                    </div>
                    <div class="column">${oglas.tekst}</div>
                </div>
            `;
        });
 
        $('#oglasi').html(oglasiHTML);
    });

There are a few things that I’d like to point out here:

  • I used the response.json() because I know that this API returns a JSON response (you can check by opening that link in the browser).
  • I used the jQuery each function to iterate over the result.
  • I used the template literals to construct the final oglasiHTML in a much cleaner way than we did that in the previous post with using concatenation.

#javascript #api #fetch #ajax

I am Developer

1615040237

PHP jQuery Ajax Post Form Data Example

PHP jquery ajax POST request with MySQL. In this tutorial, you will learn how to create and submit a simple form in PHP using jQuery ajax post request. And how to submit a form data into MySQL database without the whole page refresh or reload. And also you will learn how to show an error message to the user if the user does not fill any form field.

And this tutorial also guide on how to send data to MySQL database using AJAX + jQuery + PHP without reloading the whole page and show a client-side validation error message if it has an error in the form.

PHP jQuery AJAX POST Form Data In Into MySQL DB Example

Just follow the few below steps and easily create and submit ajax form in PHP and MySQL with client-side validation.

  • Create Database And Table
  • Create a Database Connection File
  • Create An Ajax POST Form in PHP
  • Create An Ajax Data Store File

https://www.tutsmake.com/php-jquery-ajax-post-tutorial-example/

#jquery ajax serialize form data example #submit form using ajax in php example #save form data using ajax in php #how to insert form data using ajax in php #php jquery ajax form submit example #jquery ajax and jquery post form submit example with php

I am Developer

1611112146

Codeigniter 4 Autocomplete Textbox From Database using Typeahead JS - Tuts Make

Autocomplete textbox search from database in codeigniter 4 using jQuery Typeahead js. In this tutorial, you will learn how to implement an autocomplete search or textbox search with database using jquery typehead js example.

This tutorial will show you step by step how to implement autocomplete search from database in codeigniter 4 app using typeahead js.

Autocomplete Textbox Search using jQuery typeahead Js From Database in Codeigniter

  • Download Codeigniter Latest
  • Basic Configurations
  • Create Table in Database
  • Setup Database Credentials
  • Create Controller
  • Create View
  • Create Route
  • Start Development Server

https://www.tutsmake.com/codeigniter-4-autocomplete-textbox-from-database-using-typeahead-js/

#codeigniter 4 ajax autocomplete search #codeigniter 4 ajax autocomplete search from database #autocomplete textbox in jquery example using database in codeigniter #search data from database in codeigniter 4 using ajax #how to search and display data from database in codeigniter 4 using ajax #autocomplete in codeigniter 4 using typeahead js

Alfie Mellor

Alfie Mellor

1593230166

How to Use Fetch to Make AJAX Calls in JavaScript

I will be sharing bite sized learnings about JavaScript regularly in this series. We’ll cover JS fundamentals, browsers, DOM, system design, domain architecture and frameworks.

Fetch is an interface for making an AJAX request in JavaScript. It is implemented widely by modern browsers and is used to call an API.

const promise = fetch(url, [options])

Calling fetch returns a promise, with a Response object. The promise is rejected if there is a network error, and it’s resolved if there is no problem connecting to the server and the server responded a status code. This status code could be 200s, 400s or 500s.

A sample FETCH request -

fetch(url)
.then(response => response.json())
.catch(err => console.log(err))

The request is sent as a GET by default. To send a POST / PATCH / DELETE / PUT you can use the method property as part of options parameter. Some other possible values options can take -

  • method: such as GET, POST, PATCH
  • headers: Headers object
  • mode: such as cors, no-cors, same-origin
  • cache: cache mode for request
  • credentials
  • body

#javascript #ajax #api #developer

Chumarat Pat

Chumarat Pat

1593239967

How to Use Fetch to Make AJAX Calls in JavaScript

I will be sharing bite sized learnings about JavaScript regularly in this series. We’ll cover JS fundamentals, browsers, DOM, system design, domain architecture and frameworks.

Fetch is an interface for making an AJAX request in JavaScript. It is implemented widely by modern browsers and is used to call an API.

const promise = fetch(url, [options])

Calling fetch returns a promise, with a Response object. The promise is rejected if there is a network error, and it’s resolved if there is no problem connecting to the server and the server responded a status code. This status code could be 200s, 400s or 500s.

A sample FETCH request -

fetch(url)
.then(response => response.json())
.catch(err => console.log(err))

The request is sent as a GET by default. To send a POST / PATCH / DELETE / PUT you can use the method property as part of options parameter. Some other possible values options can take -

  • method: such as GET, POST, PATCH
  • headers: Headers object
  • mode: such as corsno-corssame-origin
  • cache: cache mode for request
  • credentials
  • body

Example usage:

This example demonstrates the usage of fetch to call an API and to get a list of git repositories.

const url = 'https://api.github.com/users/shrutikapoor08/repos';

fetch(url)
  .then(response => response.json())
  .then(repos => {
    const reposList = repos.map(repo => repo.name);
    console.log(reposList);
  })
.catch(err => console.log(err))

To send a POST request, here’s how the method parameter can be used with async / await syntax.

const params = {
id: 123
}

const response = await fetch('url', {
  method: 'POST',
  headers: {
    'Content-Type': 'application/json'
  },
  body: JSON.stringify(params)
});

const data = await response.json();

#javascript #ajax