Create Chained Form Fields With ChoiceFilter.js

ChoiceFilter

ChoiceFilter is a pure Vanilla JavaScript library which creates chained dependency among select dropdown lists, checkboxes and radio buttons in a simple and an easy way. A common use case is if you select a continent from a dropdown then countries in another dropdown which relies on continents should be filtered based on the selected item, similarly countries dropdown may filter a group of checkboxes for instance a group of cities. In this case of ChoiceFilter, continents filter countries and countries filter cities, if continents dropdown is changed based on its new value the domino effect may occur and the whole chain gets affected.

Main Features
  • Pure Vanilla Javascript
  • No Dependencies
  • Simple & Easy to use
  • Single file
  • Creates chained dependency among n elements
  • Creates chained dependency among different element types e.g dropdown, checkbox, radio
  • Creates and handles Domino effect

Supports following relationships:

  • Dropdown to Dropdown
  • Dropdown to Checkbox
  • Dropdown to Radio
  • Checkbox to Checkbox
  • Checkbox to Dropdown
  • Checkbox to Radio
  • Radio to Radio
  • Radio to Checkbox
  • Radio to Dropdown

You can build dependency (relationships) like:

  • Dropdown to Checkbox to Radio to Dropdown
  • Radio to Checkbox to Dropdwon

Demo

Online demo is available!
Video demo is also available.

Get Started

Install by manual download:

Download choice-filter.js which is located in js folder and include it as follows :

 <script type="text/javascript" src="choicefilter.js"> </script>
Node

You can also install it from npm by running the following command:

npm install @rexshijaku/choicefilter

include it as:

require('@rexshijaku/choicefilter');

Usage

There are ten different examples (tutorials) on how to use this library on the demo folder. Here will be explained only one. In this example is presented a relationship between two dropdowns:

Javascript code:
    //select elements
    var continents = document.getElementById("continents"); // this will be parent elem
    var countries = document.getElementById("countries"); // this will be child (dependent)

     //create a connection between them 
    continents.filtchoices(countries, 
      {
        data:{
              "europe":["de","xk","tr"],
              "asia":["jp","tr"]
              },
          independentChoices : "select-a-country",
          autoSelectedChoicesAfterFilter: "select-a-country",
          showAllChildChoicesWhen: "all" 
      }); 
Html code:
     <select class="form-control" id="continents">
        <option value="">Select a continent</option>
         <option value="all">Europe and Asia</option>
        <option value="europe">Europe</option>
        <option value="asia">Asia</option>
      </select>
      <br>
      <select class="form-control" id="countries">
        <option value="select-a-country">Select a country</option>
        <option value="de">Germany</option>
        <option value="xk">Kosovo</option>
       	<option value="jp">Japan</option>
        <option value="tr">Turkey</option>
      </select>

Arguments

Some important arguments are briefly explained below:

Argument DataType Default Description
data key value pair array empty array Mapped data of parent and child. Which values of parent element controls which values of child.
autoFilterOnInit true or false true Whether or not change event should be triggered when the relationship is created.
independentChoices single or an array of values empty array Choices of dependent element which are not affected by filter.
showAllChildChoicesWhen single or an array of values empty array Choices in parent element which show all choices in the dependent element
autoSelectedChoicesAfterFilter single or an array of values empty array Choices in child element which should be auto-selected when filtering occurs. A common example is when you want to select a default value of a dropdown to suggest a selection, if choices were updated and previous selection does not exists anymore.
presentOnEveryParent single or an array of values empty array Choices in child element which are present in every parent. This differs from independentChoices because these will be toglle only when parent has a value.
parentControlsVisibilityOf CSS selector empty string When parent has a value these elements will be shown, when not they will not be shown.
ignoreParentValues single or an array of values empty array Ignore values which should not have an effect in filter, cases like ‘Please select an item!’
wrapperSelector CSS selector empty string Wrapper of a child choices. If child choices have wrappers, selector must be provided in this argument
valueDelimiter string “,” If your values are strings which can contain any character. You should think what value should be given as a delimiter. This values should not be present in any value of element which is used as either parent or child.

To understand these arguments more easily, please check the demo folder provided in the repository.

Support

For general questions about choicefilter.js, tweet at @rexshijaku or write me an email on rexhepshijaku@gmail.com. To have a quick tutorial check the demo folder provided in the repository.

Author

Rexhep Shijaku

Download Details:

Author: rexshijaku

Source Code: https://github.com/rexshijaku/ChoiceFilter

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Create Chained Form Fields With ChoiceFilter.js

NBB: Ad-hoc CLJS Scripting on Node.js

Nbb

Not babashka. Node.js babashka!?

Ad-hoc CLJS scripting on Node.js.

Status

Experimental. Please report issues here.

Goals and features

Nbb's main goal is to make it easy to get started with ad hoc CLJS scripting on Node.js.

Additional goals and features are:

  • Fast startup without relying on a custom version of Node.js.
  • Small artifact (current size is around 1.2MB).
  • First class macros.
  • Support building small TUI apps using Reagent.
  • Complement babashka with libraries from the Node.js ecosystem.

Requirements

Nbb requires Node.js v12 or newer.

How does this tool work?

CLJS code is evaluated through SCI, the same interpreter that powers babashka. Because SCI works with advanced compilation, the bundle size, especially when combined with other dependencies, is smaller than what you get with self-hosted CLJS. That makes startup faster. The trade-off is that execution is less performant and that only a subset of CLJS is available (e.g. no deftype, yet).

Usage

Install nbb from NPM:

$ npm install nbb -g

Omit -g for a local install.

Try out an expression:

$ nbb -e '(+ 1 2 3)'
6

And then install some other NPM libraries to use in the script. E.g.:

$ npm install csv-parse shelljs zx

Create a script which uses the NPM libraries:

(ns script
  (:require ["csv-parse/lib/sync$default" :as csv-parse]
            ["fs" :as fs]
            ["path" :as path]
            ["shelljs$default" :as sh]
            ["term-size$default" :as term-size]
            ["zx$default" :as zx]
            ["zx$fs" :as zxfs]
            [nbb.core :refer [*file*]]))

(prn (path/resolve "."))

(prn (term-size))

(println (count (str (fs/readFileSync *file*))))

(prn (sh/ls "."))

(prn (csv-parse "foo,bar"))

(prn (zxfs/existsSync *file*))

(zx/$ #js ["ls"])

Call the script:

$ nbb script.cljs
"/private/tmp/test-script"
#js {:columns 216, :rows 47}
510
#js ["node_modules" "package-lock.json" "package.json" "script.cljs"]
#js [#js ["foo" "bar"]]
true
$ ls
node_modules
package-lock.json
package.json
script.cljs

Macros

Nbb has first class support for macros: you can define them right inside your .cljs file, like you are used to from JVM Clojure. Consider the plet macro to make working with promises more palatable:

(defmacro plet
  [bindings & body]
  (let [binding-pairs (reverse (partition 2 bindings))
        body (cons 'do body)]
    (reduce (fn [body [sym expr]]
              (let [expr (list '.resolve 'js/Promise expr)]
                (list '.then expr (list 'clojure.core/fn (vector sym)
                                        body))))
            body
            binding-pairs)))

Using this macro we can look async code more like sync code. Consider this puppeteer example:

(-> (.launch puppeteer)
      (.then (fn [browser]
               (-> (.newPage browser)
                   (.then (fn [page]
                            (-> (.goto page "https://clojure.org")
                                (.then #(.screenshot page #js{:path "screenshot.png"}))
                                (.catch #(js/console.log %))
                                (.then #(.close browser)))))))))

Using plet this becomes:

(plet [browser (.launch puppeteer)
       page (.newPage browser)
       _ (.goto page "https://clojure.org")
       _ (-> (.screenshot page #js{:path "screenshot.png"})
             (.catch #(js/console.log %)))]
      (.close browser))

See the puppeteer example for the full code.

Since v0.0.36, nbb includes promesa which is a library to deal with promises. The above plet macro is similar to promesa.core/let.

Startup time

$ time nbb -e '(+ 1 2 3)'
6
nbb -e '(+ 1 2 3)'   0.17s  user 0.02s system 109% cpu 0.168 total

The baseline startup time for a script is about 170ms seconds on my laptop. When invoked via npx this adds another 300ms or so, so for faster startup, either use a globally installed nbb or use $(npm bin)/nbb script.cljs to bypass npx.

Dependencies

NPM dependencies

Nbb does not depend on any NPM dependencies. All NPM libraries loaded by a script are resolved relative to that script. When using the Reagent module, React is resolved in the same way as any other NPM library.

Classpath

To load .cljs files from local paths or dependencies, you can use the --classpath argument. The current dir is added to the classpath automatically. So if there is a file foo/bar.cljs relative to your current dir, then you can load it via (:require [foo.bar :as fb]). Note that nbb uses the same naming conventions for namespaces and directories as other Clojure tools: foo-bar in the namespace name becomes foo_bar in the directory name.

To load dependencies from the Clojure ecosystem, you can use the Clojure CLI or babashka to download them and produce a classpath:

$ classpath="$(clojure -A:nbb -Spath -Sdeps '{:aliases {:nbb {:replace-deps {com.github.seancorfield/honeysql {:git/tag "v2.0.0-rc5" :git/sha "01c3a55"}}}}}')"

and then feed it to the --classpath argument:

$ nbb --classpath "$classpath" -e "(require '[honey.sql :as sql]) (sql/format {:select :foo :from :bar :where [:= :baz 2]})"
["SELECT foo FROM bar WHERE baz = ?" 2]

Currently nbb only reads from directories, not jar files, so you are encouraged to use git libs. Support for .jar files will be added later.

Current file

The name of the file that is currently being executed is available via nbb.core/*file* or on the metadata of vars:

(ns foo
  (:require [nbb.core :refer [*file*]]))

(prn *file*) ;; "/private/tmp/foo.cljs"

(defn f [])
(prn (:file (meta #'f))) ;; "/private/tmp/foo.cljs"

Reagent

Nbb includes reagent.core which will be lazily loaded when required. You can use this together with ink to create a TUI application:

$ npm install ink

ink-demo.cljs:

(ns ink-demo
  (:require ["ink" :refer [render Text]]
            [reagent.core :as r]))

(defonce state (r/atom 0))

(doseq [n (range 1 11)]
  (js/setTimeout #(swap! state inc) (* n 500)))

(defn hello []
  [:> Text {:color "green"} "Hello, world! " @state])

(render (r/as-element [hello]))

Promesa

Working with callbacks and promises can become tedious. Since nbb v0.0.36 the promesa.core namespace is included with the let and do! macros. An example:

(ns prom
  (:require [promesa.core :as p]))

(defn sleep [ms]
  (js/Promise.
   (fn [resolve _]
     (js/setTimeout resolve ms))))

(defn do-stuff
  []
  (p/do!
   (println "Doing stuff which takes a while")
   (sleep 1000)
   1))

(p/let [a (do-stuff)
        b (inc a)
        c (do-stuff)
        d (+ b c)]
  (prn d))
$ nbb prom.cljs
Doing stuff which takes a while
Doing stuff which takes a while
3

Also see API docs.

Js-interop

Since nbb v0.0.75 applied-science/js-interop is available:

(ns example
  (:require [applied-science.js-interop :as j]))

(def o (j/lit {:a 1 :b 2 :c {:d 1}}))

(prn (j/select-keys o [:a :b])) ;; #js {:a 1, :b 2}
(prn (j/get-in o [:c :d])) ;; 1

Most of this library is supported in nbb, except the following:

  • destructuring using :syms
  • property access using .-x notation. In nbb, you must use keywords.

See the example of what is currently supported.

Examples

See the examples directory for small examples.

Also check out these projects built with nbb:

API

See API documentation.

Migrating to shadow-cljs

See this gist on how to convert an nbb script or project to shadow-cljs.

Build

Prequisites:

  • babashka >= 0.4.0
  • Clojure CLI >= 1.10.3.933
  • Node.js 16.5.0 (lower version may work, but this is the one I used to build)

To build:

  • Clone and cd into this repo
  • bb release

Run bb tasks for more project-related tasks.

Download Details:
Author: borkdude
Download Link: Download The Source Code
Official Website: https://github.com/borkdude/nbb 
License: EPL-1.0

#node #javascript

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How to Create a Client-Side Form Validation using JavaScript

In this video, we will create a client-side form validation using JavaScript. I'll only use Vanilla JavaScript and no external 3rd party dependencies. The aim is to help beginners to do form validation and understand how the whole process works.

Timestamps:
00:00 Intro
00:26 HTML
03:33 CSS
05:35 Javascript

Source code: https://codepen.io/javascriptacademy-stash/pen/oNeNMNR


 HTML

Let's start with the HTML markup. We'll have a container div, that we'll use to position and style our form. Inside that, not surprisingly, we'll create a form, we also set an id for it, and set the action to / since we don't really want to submit this form.

We'll create four input fields, for the username, email, password, and password confirmation. For styling and control purposes we'll wrap these input tags into divs with the class input control. Each of these input controls will contain a label, an input, and a div with the class error. Every input should have an id and name attribute. The label's should have a matching for property with the corresponding input tag's name attribute. For the input type we will use text for the username and email, and use password for the password and the password confirmation. The div with the error class will hold the error messages for the specific input field. It will be empty for now, we will modify it from javascript.

Lastly, we have to add a button to "submit" our form. In this example we won't really submit the form just simulate it. For the submit button I'll use a button with a type of submit.

<div class="container">
        <form id="form" action="/">
            <h1>Registration</h1>
            <div class="input-control">
                <label for="username">Username</label>
                <input id="username" name="username" type="text">
                <div class="error"></div>
            </div>
            <div class="input-control">
                <label for="email">Email</label>
                <input id="email" name="email" type="text">
                <div class="error"></div>
            </div>
            <div class="input-control">
                <label for="password">Password</label>
                <input id="password"name="password" type="password">
                <div class="error"></div>
            </div>
            <div class="input-control">
                <label for="password2">Password again</label>
                <input id="password2"name="password2" type="password">
                <div class="error"></div>
            </div>
            <button type="submit">Sign Up</button>
        </form>
    </div>

That is the HTML markup that we need for our form. Let's style it a bit with CSS.

CSS

We'll give a simple clean spacious design for this tutorial. I'll set a linear gradient as the background and I'll use a custom google font, that you can install from here.

body {
    background: linear-gradient(to right, #0f2027, #203a43, #2c5364);
    font-family: 'Poppins', sans-serif;
}

We'll give a fix width to our form, and center it with margins, also I'll give it a top margin to move it down a bit vertically. To have more space we apply 20px of padding. We'll set a fixed font size, a light background color and also set a border radius to have rounded corners.

#form {
    width: 300px;
    margin: 20vh auto 0 auto;
    padding: 20px;
    background-color: whitesmoke;
    border-radius: 4px;
    font-size: 12px;
}

For the form title, we'll use a dark text color, and center it horizontally using text-align: center. The submit button should stand out so we'll use a blue background color, and white text color. We also remove the browser default borders and give it a little border-radius. We'll give it a little spacing with paddings and margins, and make it full-width by applying 100% width.

#form h1 {
    color: #0f2027;
    text-align: center;
}

#form button {
    padding: 10px;
    margin-top: 10px;
    width: 100%;
    color: white;
    background-color: rgb(41, 57, 194);
    border: none;
    border-radius: 4px;
}

To have the inputs stacked below each other we'll use flexbox. To do that we'll set display: flex; and flex-direction: column. For the inputs we'll set a grey border, with a little border-radius. We'll set the display property to block, and make them full-width, by applying width 100%. We'll also set a little padding, so it'll be more spacious. I'll also remove the outline when the input is in focus, by setting outline: 0.

.input-control {
    display: flex;
    flex-direction: column;
}

.input-control input {
    border: 2px solid #f0f0f0;
    border-radius: 4px;
    display: block;
    font-size: 12px;
    padding: 10px;
    width: 100%;
}

.input-control input:focus {
    outline: 0;
}

We'll use two classes ("success" and "error") to give visual feedback to the user on whether the input's value is valid or not. We'll apply these classes from javascript to the input-control div which contains the specific input field. When the success class is present we will set a green border color, otherwise if error is present we'll use a red border color instead. For the error div we'll use a smaller font-size and a red color to show the error messages.

.input-control.success input {
    border-color: #09c372;
}

.input-control.error input {
    border-color: #ff3860;
}

.input-control .error {
    color: #ff3860;
    font-size: 9px;
    height: 13px;
}

Let's do the validation in javascript next!

Javascript

The first thing we have to do is to save references for the form, and the input fields. As we gave id for every input and the form we can easily to do by using getElementById.

const form = document.getElementById('form');
const username = document.getElementById('username');
const email = document.getElementById('email');
const password = document.getElementById('password');
const password2 = document.getElementById('password2');

To prevent the form for automatically submit we have to attach and event listener to our form's submit event. In this event handler function we have to call preventDefault() function to prevent the form from submitting automatically. Instead of submitting we'll call the validateInputs function, which will validate the inputs and if we want to we can submit the form in there after every check passes, but we won't do that in this tutorial. We'll create this validateInputs shortly.

form.addEventListener('submit', e => {
    e.preventDefault();

    validateInputs();
});

We'll also create two helper functions: setErrorsetSuccess. We'll use these helper functions to set the error or success states of the input controls. Let's start with the setError one. It receives two parameters: element, and message. The element will be the input element that is in the specific input-control. So first we have to get the input control parent div. We'll save it into the inputControl variable, and get the input control div by using the parent property of the input element. Next we have to gather the error div, and save it into a variable. We can do that by querying the input control with the error class.
Now we have to set the error div's innerText to be the message that we got in parameters, and remove the success class from the input control (if it exists) and add the error class.

const setError = (element, message) => {
    const inputControl = element.parentElement;
    const errorDisplay = inputControl.querySelector('.error');

    errorDisplay.innerText = message;
    inputControl.classList.add('error');
    inputControl.classList.remove('success')
}

The setSuccess method will be really similar. The first difference is that it won't receive a message as a parameter. We have to clear the error display by setting its innerText to an empty string. Lastly we have to reverse the class application. We'll add the success class to the inputControl and remove the error class (if present).

const setSuccess = element => {
    const inputControl = element.parentElement;
    const errorDisplay = inputControl.querySelector('.error');

    errorDisplay.innerText = '';
    inputControl.classList.add('success');
    inputControl.classList.remove('error');
};

We will create one last helper function to validate emails. This is an optional step, if you don't want to use regular expressions, feel free to just set the input type of the email field to email. The isValidEmail function will take a string as a parameter and use this weird looking regular expression to check whether it is a valid email or not. We'll use String.test() function to test the string against the regex. We'll also convert the email to a string and make it lowercase.

const isValidEmail = email => {
    const re = /^(([^<>()[\]\\.,;:\s@"]+(\.[^<>()[\]\\.,;:\s@"]+)*)|(".+"))@((\[[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\])|(([a-zA-Z\-0-9]+\.)+[a-zA-Z]{2,}))$/;
    return re.test(String(email).toLowerCase());
}

Now we should create the validator validateInputs function. First we will get the value of all the input fields. We can do that by getting the value property's value of the input field references. We'll call the String.trim() function to remove the trailing empty spaces (if any) from the start and end of the values.
Then we can start validating inputs. We'll use if, else statements to do the validation. For the username we will check whether if it is empty or not, by comparing the value with an empty string. If it empty, we'll call the setError function and provide the username element to it, with our error message. Otherwise we'll call the setSuccess method with the username element. Now we have to do this for the other input fields, but the approach will be the same.

const validateInputs = () => {
    const usernameValue = username.value.trim();
    const emailValue = email.value.trim();
    const passwordValue = password.value.trim();
    const password2Value = password2.value.trim();

    if(usernameValue === '') {
        setError(username, 'Username is required');
    } else {
        setSuccess(username);
    }
};

For the email we'll check if it is provided or not, and set an error if it is empty. If it is not empty we'll check whether it is a valid email address, and if not we'll set an error, otherwise we set success for the field.

if(emailValue === '') {
        setError(email, 'Email is required');
    } else if (!isValidEmail(emailValue)) {
        setError(email, 'Provide a valid email address');
    } else {
        setSuccess(email);
    }
}

For the password we'll check whether it is empty or not, and if it is not empty we'll check if it is longer than 7 characters. If not, well set an error, otherwise we'll set it as success.

if(passwordValue === '') {
        setError(password, 'Password is required');
    } else if (passwordValue.length < 8 ) {
        setError(password, 'Password must be at least 8 character.')
    } else {
        setSuccess(password);
    }
}

For the password confirmation we'll check if it is empty, and we should also check if the password confirmation's value is equal to the password's value.

if(password2Value === '') {
        setError(password2, 'Please confirm your password');
    } else if (password2Value !== passwordValue) {
        setError(password2, "Passwords doesn't match");
    } else {
        setSuccess(password2);
    }
}

Now we have every input validated, if we wanted to we could submit our form now to a specific endpoint.

Good job now you have a working form validation Javascript. Please note that you always have to validate the form inputs on the server-side as client-side validation can be easily bypassed. There are way more advanced form validation methods and libraries that we use in modern web development, but this project is a really good way to start and learn the fundamentals.

#javascript

Upload, Preview & Download Images using JavaScript & PHP

In this guide, you’ll learn how to Upload, Preview & Download Images using JavaScript & PHP.

To create Upload, Preview & Download Images using JavaScript & PHP. First, you need to create two Files one PHP File and another one is CSS File.

1: First, create a PHP file with the name of index.php

 

<?php
//if download button clicked
if(isset($_POST['downloadBtn'])){
    //getting the user img url from input field
    $imgURL = $_POST['file']; //storing in variable
    $regPattern = '/\.(jpe?g|png|gif|bmp)$/i'; //pattern to validataing img extension
    if(preg_match($regPattern, $imgURL)){ //if pattern matched to user img url
        $initCURL = curl_init($imgURL); //intializing curl
        curl_setopt($initCURL, CURLOPT_RETURNTRANSFER, true);
        $downloadImgLink = curl_exec($initCURL); //executing curl
        curl_close($initCURL); //closing curl
        // now we convert the base 64 format to jpg to download
        header('Content-type: image/jpg'); //in which extension you want to save img
        header('Content-Disposition: attachment;filename="image.jpg"'); //in which name you want to save img
        echo $downloadImgLink;
    }
}
?>
<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Image Download in PHP | Codequs</title>
    <link rel="stylesheet" href="style.css">
    <link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/font-awesome/5.15.3/css/all.min.css"/>
    <script src="https://code.jquery.com/jquery-3.5.1.min.js"></script>
</head>
<body>
    <div class="wrapper">
        <div class="preview-box">
            <div class="cancel-icon"><i class="fas fa-times"></i></div>
            <div class="img-preview"></div>
            <div class="content">
                <div class="img-icon"><i class="far fa-image"></i></div>
                <div class="text">Paste the image url below, <br/>to see a preview or download!</div>
            </div>
        </div>
        <form action="index.php" method="POST" class="input-data">
            <input id="field" type="text" name="file" placeholder="Paste the image url to download..." autocomplete="off">
            <input id="button" name="downloadBtn" type="submit" value="Download">
        </form>
    </div>
    <script>
        $(document).ready(function(){
            //if user focus out from the input field
            $("#field").on("focusout", function(){
                //getting user entered img URL
                var imgURL = $("#field").val();
                if(imgURL != ""){ //if input field isn't blank
                    var regPattern = /\.(jpe?g|png|gif|bmp)$/i; //pattern to validataing img extension
                    if(regPattern.test(imgURL)){ //if pattern matched to image url
                        var imgTag = '<img src="'+ imgURL +'" alt="">'; //creating a new img tag to show img
                        $(".img-preview").append(imgTag); //appending img tag with user entered img url
                        // adding new class which i've created in css
                        $(".preview-box").addClass("imgActive");
                        $("#button").addClass("active");
                        $("#field").addClass("disabled");
                        $(".cancel-icon").on("click", function(){
                            //we'll remove all new added class on cancel icon click
                            $(".preview-box").removeClass("imgActive");
                            $("#button").removeClass("active");
                            $("#field").removeClass("disabled");
                            $(".img-preview img").remove();
                            // that's all in javascript/jquery now the main part is PHP
                        });
                    }else{
                        alert("Invalid img URL - " + imgURL);
                        $("#field").val('');//if pattern not matched we'll leave the input field blank
                    }
                }
            });
        });
    </script>
    
</body>
</html>

 

2: Second, create a CSS file with the name of style.css

 

@import url('https://fonts.googleapis.com/css2?family=Poppins:wght@200;300;400;500;600;700&display=swap');
*{
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Poppins', sans-serif;
}
html,body{
    display: grid;
    height: 100%;
    place-items: center;
}
::selection{
   color: #fff;
   background: #4158d0;    
}
.wrapper{
    height: 450px;
    width: 500px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    flex-direction: column;
}
.wrapper .preview-box{
    position: relative;
    width: 100%;
    height: 320px;
    display: flex;
    text-align: center;
    align-items: center;
    justify-content: center;
    border-radius: 5px;
    border: 2px dashed #c2cdda;
}
.preview-box.imgActive{
    border: 2px solid transparent;
}
.preview-box .cancel-icon{
    position: absolute;
    right: 20px;
    top: 10px;
    z-index: 999;
    color: #4158d0;
    font-size: 20px;
    cursor: pointer;
    display: none;
}
.preview-box.imgActive:hover .cancel-icon{
    display: block;
}
.preview-box .cancel-icon:hover{
    color: #ff0000;
}
.preview-box .img-preview{
    height: 100%;
    width: 100%;
    position: absolute;
}
.preview-box .img-preview img{
    height: 100%;
    width: 100%;
    border-radius: 5px;
}
.wrapper .preview-box .img-icon{
    font-size: 100px;
    background: linear-gradient(-135deg, #c850c0, #4158d0);
    background-clip: text;
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}
.wrapper .preview-box .text{
    font-size: 18px;
    font-weight: 500;
    color: #5B5B7B;
}
.wrapper .input-data{
    height: 130px;
    width: 100%;;
    display: flex;
    align-items: center;
    justify-content: space-evenly;
    flex-direction: column;
}
.wrapper .input-data #field{
    width: 100%;
    height: 50px;
    outline: none;
    font-size: 17px;
    padding: 0 15px;
    user-select: auto;
    border-radius: 5px;
    border: 2px solid lightgrey;
    transition: all 0.3s ease;
}
.input-data #field.disabled{
    color: #b3b3b3;
    pointer-events: none;
}
.wrapper .input-data #field:focus{
    border-color: #4158d0;
}
.input-data #field::placeholder{
    color: #b3b3b3;
}
.wrapper .input-data #button{
    height: 50px;
    width: 100%;
    border: none;
    outline: none;
    color: #fff;
    font-weight: 500;
    font-size: 18px;
    cursor: pointer;
    border-radius: 5px;
    opacity: 0.5;
    pointer-events: none;
    background: linear-gradient(-135deg, #c850c0, #4158d0);
    transition: all 0.3s ease;
}
.input-data #button.active{
    opacity: 1;
    pointer-events: auto;
}
.input-data #button:active{
    transform: scale(0.99);
}

Now you’ve successfully created a How to Upload, Preview & Download Image using JavaScript & PHP.