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Dynamically add <img> tags with via PHP loop, via calling a JavaScript function on each loop

I have a PHP function that loops through image results in a database, formats them with HTML, then returns the variable containing the HTML layout to my page.php. This is all working okay, but in the loop I have some script tags that call a function in my script.js file. It takes two parameters (url and count). I am trying to pass the url of the result from the database to the function, create a new img element, and append the passed url to the src attribute of the newly created img tag.
This appears to be working so far - when I console.log the result, I get a load of <img> tags, all with corresponding src attached to them.
I am having trouble with actually getting these back to the front end, though.
My code below shows the part of the php that gets looped through, followed be the Javascript function it calls on each loop.
public function getResultsHtml($page, $pageSize, $term) {
$fromLimit = ($page - 1) * $pageSize;
$query = $this->con->prepare("SELECT * FROM images
WHERE (title LIKE :term
OR alt LIKE :term) AND broken=0
ORDER BY clicks DESC
LIMIT :fromLimit, :pageSize");
$searchTerm = "%" . $term . "%";
$query->bindParam(":term", $searchTerm);
$query->bindParam(":fromLimit", $fromLimit, PDO::PARAM_INT);
$query->bindParam(":pageSize", $pageSize, PDO::PARAM_INT);
$query->execute();
$resultsHtml = "<div class='image-results'>";
$count = 0;
while($row = $query->fetch(PDO::FETCH_ASSOC)) {
$count++;
$id = $row["id"];
$imgUrl = $row["imgUrl"];
$siteUrl = $row["siteUrl"];
$title = $row["title"];
$alt = $row["alt"];
if($title){
$displayText = $title;
} else if ($alt) {
$displayText = $alt;
} else {
$displayText = $imgUrl;
}
$resultsHtml .= "<div class='grid-item image$count'>
<a href='$imgUrl'>
<script>
document.addEventListener('DOMContentLoaded', function() {
loadImage(\"$imgUrl\", \"image$count\");
});
</script>
<span class='details'>$displayText</span>
</a>
</div>";
}
$resultsHtml .= "</div>";
return $resultsHtml;
}
var loadImage = function(src, className){
var image = document.createElement("img");
var aTag = document.querySelectorAll("." + className + " a");
image.onload = function(){
aTag.innerHTML = image;
};
image.onerror = function(){
};
image.setAttribute("src", src);
}
At the moment I'm not geting any results at the front end. In the page source, I can see that inside each anchor tag are script tags, which show the function preloaded with the parameters (loadImage(http://www.com, image22)), but it isn't actually getting a return from the function.
The solution for this with jQuery is below, but I really don't want to use jQuery!
function loadImage(src, className) {
var image = $("<img>");
image.on("load", function() {
$("." + className + " a").append(image);
});
image.on("error", function() {
});
image.attr("src", src);
}
I know that there is some trouble with dynamically writing <script> tags with .innerHTML, but I don't think this is the problem as the script tags are written before the function is called.
I think I have something firing in the wrong order, or I'm missing something that jQuery handles automatically with the .append function.
I have also tried aTag.appendChild(image);, which also gives no results.
I have been using jQuery for a few months, but I am trying to learn Vanilla JS thoroughly - I'm trying to grasp how the jQuery functions actually work, rather than just relying on them blindly.
Any help is massively appreciated!

Beware of that querySelectorAll() returns an array-like NodeList (https://developer.mozilla.org/en-US/docs/Web/API/NodeList), so it should be like this:
(If you only want one element returned user querySelector(), then you don't need the loop)
function loadImage(src, className) {
var image = document.createElement("img");
image.src = src;
image.onload = function() {
var tags = document.querySelectorAll("." + className + " a");
for (var i = 0; i < tags.length; i++) {
tags[i].appendChild(image);
}
}
}
<div class='grid-item image2'>
<a href='https://cdn.pixabay.com/photo/2015/08/21/21/55/star-wars-899693_960_720.jpg'>
<script>
document.addEventListener('DOMContentLoaded', function() { loadImage("https://cdn.pixabay.com/photo/2015/08/21/21/55/star-wars-899693_960_720.jpg", "image2");
});
</script>
<span class='details'>Star Wars 1</span>
</a>
</div>

The problem is that you are using querySelectorAll, which returns a NodeList instead of a single DOM node. This means, you have to iterate over the NodeList and append the image to all the nodes within. For this, you have can either create new copies for each place you want to insert the image, or use cloneNode multiple times.
var each = function (xs, func) {
for (var i = 0; i < xs.length; i += 1) {
func(xs[i]);
}
return xs;
}
var loadImage = function(src, className){
var image = document.createElement("img");
var aTag = document.querySelectorAll("." + className + " a");
image.onload = function(){
each(aTag, function (a) {
a.appendChild(image.cloneNode());
});
};
image.onerror = function(){};
image.alt = '';
image.src = src;
}
loadImage('http://www.fillmurray.com/500/300', 'wrap')
<div class="wrap">
</div>

Get value from a JSON file with multi dimensional array using jQuery $.getJSON method

I've been trying to fetch some values from a JSON file using the $.getJSON method. The first two loops are static so I wrote the below code to fetch the value of "layers.name". From the third loop, the data in the layers may or may not be available. How can I fetch the value of all "layers.name"presented in the JSON file
PS: The JSON file is an output generated from a software where the layer is presented
in this format
Here the code I've worked so far where I get the first two loop layers.
Html
<body>
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.2.1/jquery.min.js"></script>
<script src="test.js"></script>
</body>
Javscript
$.getJSON('https://api.myjson.com/bins/6atbz', function(data) {
var layer = data.layers.reverse()
for (i=0; i<layer.length; i ++){
name = data.layers[i].name
id= data.layers[i].do_objectID
var className = '.'+id
var main = "<div class=\""+id+"\" data-number=\""+i+"\">"+name+"<\/div>"
$('body').append(main);
var subLayer = data.layers[i].layers.reverse()
for(j=0; j<subLayer.length; j++){
newname = data.layers[i].layers[j].name
$().append(' '+newname);
var subsubLayer = data.layers[i].layers[j]
var sub = "<div class=\""+newname+"\" data-number=\""+j+"\">"+newname+"<\/div>"
$(className).append(sub);
}
}
})
Thanks
Link to Fiddle

I think it's a good idea use recursion. Here is example:
var container = document.getElementById("container");
$.getJSON('https://api.myjson.com/bins/6atbz', function(data) {
buildTree(data, container)
})
function buildTree (node, container) {
var layers = node.layers || [];
console.info(node);
layers.forEach(function(item) {
var newContainer = document.createElement('div');
var span = document.createElement('span');
span.innerHTML = item.name;
newContainer.appendChild(span);
container.appendChild(newContainer);
if(item.layers){
buildTree(item, newContainer)
}
});
}
Here is live demo

Extracting images from RSS/Atom feeds

I'm wondering how to extract images from RSS and Atom feeds so I can use them as a thumbnail when display the feed in a container with it's relative Title, Description and Link. So far my code, (shown below), grabs images from only certain feed types, I'm wondering how I can grab every image my script comes across.
if (feed_image_type == "description") {
item_img = $($(this).find('description').text()).find("img").attr("src");
} else if (feed_image_type == "encoded") {
item_img = $($(this).find('encoded').text()).find("img").attr("src");
} else if (feed_image_type == "thumbnail") {
item_img = $(this).find('thumbnail').attr('url');
} else {
item_img = $(this).find('enclosure').attr('url');
}
For example, I cannot figure out how I would grab the image link from the code rss feed snippet below:
<description>
<![CDATA[
<img src="https://i.kinja-img.com/gawker-media/image/upload/s--E93LuLOd--/c_fit,fl_progressive,q_80,w_636/hd6cujrvf1d72sbxsbnr.jpg" /><p>With a surprise showing of skill and, at one point, a miracle, the bottom-ranked team in the European <em>League </em>Championship Series will not end the summer winless.<br></p><p>Read more...</p>
]]>
</description>

Using these sources:
parse html inside cdata using jquery or javascript
jQuery.parseXML
https://www.w3schools.com/xml/dom_cdatasection.asp
It is essential that you get your content correctly as XML, by setting the dataType to 'xml'.
This code is self-contained and works:
var xmlString = '<Customer><![CDATA[ <img src="y1" /> ]]></Customer>';
var xmlObj = $.parseXML(xmlString);
var cdataText = xmlObj.firstChild.firstChild.textContent;
var jqueryObj = $(cdataText);
var imgUrl = jqueryObj.find('img').attr('src');
console.log(imgUrl);
This is slightly imprecise because you don't give quite enough information to exactly reproduce your situation. I will start as though this from your question is the only part of your code:
if (feed_image_type == "description") {
item_img = $($(this).find('description').text()).find("img").attr("src");
}
This ought to get close:
if (feed_image_type == "description") {
var cdataText = $(this).firstChild.firstChild.textContent;
var jqueryObj = $(cdataText);
item_img = jqueryObj.find('img').attr('src');
}

You can also try this.
let str = `<description>
<![CDATA[
<img src="https://i.kinja-img.com/gawker-media/image/upload/s--E93LuLOd--/c_fit,fl_progressive,q_80,w_636/hd6cujrvf1d72sbxsbnr.jpg" /><p>With a surprise showing of skill and, at one point, a miracle, the bottom-ranked team in the European <em>League </em>Championship Series will not end the summer winless.<br></p><p>Read more...</p>
]]>
</description>`;
//We need to strip CDATA in our case. Otherwise the parser will not parse the contents inside it.
str = str.replace("<![CDATA[", "").replace("]]>", "")
let parser = new DOMParser();
let xmlDoc = parser.parseFromString(str,"text/xml");
let images = [...xmlDoc.querySelectorAll('img')].map(image=>image.getAttribute('src'))

How to display images using Javascript and JSON

I have to display images to the browser and I want to get the image from a JSON response and display it to the browser using Javascript. This is what the JSON response looks like:
[{
"0":"101",
"member_id":"101",
"1":"3k.png",
"image_nm":"3k.png",
"2":"\/images\/phones\/",
"image_path":"\/images\/"
},{
"0":"102",
"member_id":"102",
"1":"mirchi.png",
"image_nm":"mirchi.png",
"2":"images\/phones\/",
"image_path":"images\/phones\/"
},{
"0":"103",
"member_id":"103",
"1":"masti.png",
"image_nm":"masti.png",
"2":"images\/phones\/",
"image_path":"images\/phones\/"
}]
How do I do this (I am a beginner)?
here is the code what i wrote...
var jsonString = '[{"0":"101","member_id":"101","1":"3k.png","image_nm":"3k.png","2":"\/images\/phones\/","image_path":"\/images\/phones\/"},{"0":"102","member_id":"102","1":"mirchi.png","image_nm":"mirchi.png","2":"images\/phones\/","image_path":"images\/phones\/"},{"0":"103","member_id":"103","1":"masti.png","image_nm":"masti.png","2":"images\/phones\/","image_path":"images\/phones\/"}]';
var obj = JSON.parse(jsonString);
for(var i = 0, len = obj.length; i < len; i++){
var img = new Image();
img.setAttribute("src",obj[i][2] + obj[i][1]);
document.body.appendChild(img);
}

Assuming you parsed your json in a variable called json, this would add all images in a container with id yourcontainer:
var images = '';
for( var i=0, max<json.length; ++i ) {
images += '<img src="' + json[i]['image_path'] + json[i]['image_nm'] + '" />';
}
document.getElementById( 'yourcontainer' ).innerHTML = images;

Seems pretty straight forward. If this is json_encoded, then we can use json[key] to get the value, if you aren't familiar with the term 'key', json encodes arrays in the key:value, format, so for this, if we used json[member_id], we would get '101', if we used json[image_nm], we would get '3k.png', putting this all together it seems as if it's pretty well separated, you just have to know what goes where. I have an idea, but not 100%,I would expect you to do something like
var myImages = '';
for(var i = 0; i < json.length; i++){
myImages += '<img src="'+json[i]['image_path']+json[i]['img_nm']+'" />';
}
document.getElementById('myImgHolder').innerHTML = myImages;
Based on your json data, this would evaluate a variable and test it against the length of the json array. The statement also declares that while the variable is less than the total length of the json array, we will iterate to the next object. We would expect output along the format of -
<img src="/images/3k.png" />.
Then it would take the new images and place them in a Div with the id of myImgHolder.
Hope this helps.
EDIT 1
If you don't have a container to place these images inside of it, then you will need to create the container and place it somewhere.
var myImgHolder = document.createElement('div');
myImgHolder.setAttribute("id", "myImgHolder");
document.getElementById('ICanTargetThis').appendChild(myImgHolder);
The above code sets the variable myImgHolder to the creation of a new DIV element. Then, using the variable, we declare the attribute "id" to set as 'myImgHolder'. Now we have the element. But what do we do with it? Well we MUST target an existing element within our page, even if we're just targeting the tag...something. then we use the .appendChild method and use our variable...appendChild(myImgHolder);

You can use jQuery here.
Add following script in the head tag.
<script src="https://code.jquery.com/jquery-2.1.1.min.js"></script>
<script>
$(document).ready(function () {
var url = "entries.json";
$.getJSON(url, function (url){
var img= "";
$.each(url, function () {
img += '<li><img src= "' + this.images+ '"></li>';
});
$('body').append(img);
});
});
</script>

Get source of image

I have a next string like:
<img src="../uplolad/commission/ranks/avatar.jpg' . $row[$c_name] .'" width="50" height="50"/>
How can i get a image file name in javascript? I know only PHP regexes. Extention of a file can be different.
The result must be: avatar.jpg

Regex is not ideal for this. JavaScript can traverse the HTML as distinct objects more readily than as a long string. If you can identify the picture by anything, say by adding an ID to it, or an ID to a parent with that as the only image, you'll be able to access the image from script:
var myImage = document.getElementById('imgAvatar'); // or whatever means of access
var src = myImage.src; // will contain the full path
if(src.indexOf('/') >= 0) {
src = src.substring(src.lastIndexOf('/')+1);
}
alert(src);
And if you want to edit, you can do that just as well
myImage.src = src.replace('.jpg', '.gif');

Fetch it following coding which can help what you want to get.
<script type="text/javascript">
function getImageName(imagePath) {
var objImage = new RegExp(/([^\/\\]+)$/);
var getImgName = objImage.exec(imagePath);
if (getImgName == null) {
return null;
}
else {
return getImgName[0];
}
}
</script>
<script>
var mystring = getImageName("http://www.mypapge.mm/myimage.png")
alert(mystring)
</script>

Here's a shorter variation of David Hedlund's answer that does use regex:
var myImage = document.getElementById('imgAvatar'); // or whatever means of access
alert(myImage.src.replace( /^.+\// , '' ));