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Connect function to pictures displayed from a PC folder

I'm pretty new to JS and programming altogether so I'm sorry in advance if the explanation is a little sloppy, but I'll try to make it as clear as possible.
So what I'm trying to do is have a JS code that reads and displays (in an HTML page) photos from a PC folder, makes them clickable and on the click it redirects you to a page with the same photo but in high resolution.
Now, I have this piece of code that displays the said pictures, but the thing is I don't seem to be able to figure out how to "connect" it to the pictures and make them clickable. What makes it more difficult is that I'm trying to make all of this code dynamic (as you can see I've done in the below code), so I would like not to have any hardcoded titles of pictures and so on.
var index = 1;
var tempImg = new Image();
tempImg.onload = function(){
appendImage();
}
var tryLoadImage = function(index){
tempImg.src = 'img/' + index + '.jpg';
}
var appendImage = function(){
var img = document.createElement('img');
img.src = tempImg.src;
document.body.appendChild(img)
tryLoadImage(index++);
}
tryLoadImage(index);
Any help is very much appreciated, thank you very much!

You can make your images clickable by adding an onclick function to them. Try something like this:
var appendImage = function(){
var img = document.createElement('img');
img.src = tempImg.src;
img.onclick = e => {
// do something you want to show the full picture like this maybe
var el = document.getElementById("fullpictureid");
if (el && e.target.src) {
el.src = e.target.src;
// so that it sets "src" in <img id="fullpictureid"> for example
}
};
document.body.appendChild(img)
tryLoadImage(index++);
}

Automatically load an image using javascript

I'm using this code to build a gallery:
window.onload=function(){
var image = document.getElementsByClassName('thumbnails')[0].getElementsByTagName('img');
var mainImage = document.getElementById('rr_lrg_img');
[].forEach.call(image,function(x){
x.onmouseover = function(){
mainImage.src = x.src;
};
});
}
The code loads different thumbnails on the big image when "onmouseover". Now I would like to "preload" the first image from that gallery of thumbnails. I tried using onload with
rr_lrg_img.src=document.getElementsByClassName('thumbnails')[0].getElementsByTagName('img')[0].src
but then it conflicts with the onmouseover. Any ideas? I can only use javascript, no jquery.

Since your var image is actually a collection of images, you need to use the [0] index pointer to target the first one:
window.onload=function(){
var image = document.getElementsByClassName('thumbnails')[0].getElementsByTagName('img');
var mainImage = document.getElementById('rr_lrg_img');
mainImage.src = image[0].src; // Add this line (preload first image into main one)
function toMainImage() {
mainImage.src = this.src;
}
[].forEach.call(image,function(x){
x.addEventListener("mouseenter", toMainImage, false);
});
}
.thumbnails img{height:50px;}
<img src="//placehold.it/200x200&text=default" id="rr_lrg_img">
<div class="thumbnails">
<img src="//placehold.it/200x200/cf5&text=1">
<img src="//placehold.it/200x200/f0f&text=2">
<img src="//placehold.it/200x200/444&text=3">
</div>

Dynamically add pictures using javascript.

I've been working on a flowchart type program that changes various parts of the html each time a new question is posed (this question is represented by the 'state' variable below), things like Title, description and images.
Currently, my HTML for the images is:
<a id="imageLink" target="_blank" href=""><img class= 'right' id= 'imageBox' style ='max-height:50%;' src='' /></a>
<h3 id ='imageBoxText' ></h3>
and the image link and the legend for the image are found in imageArray which looks something like this:
imageArray = {'questionOne': ['www.link to image.com,'Legend for image']}
In this case 'questionOne' would be 'state'.
So far, I can load a single image asynchronously using:
document.getElementById("imageBox").src = "http://www.ktcagency.com/img/loader.gif"; // load spinner
var img = new Image(); // load image asynchronously
var newsrc = imageArray[state][0];
img.onload = function () { // onload handler
document.getElementById("imageBox").src = newsrc;
};
img.src = newsrc;
I also add the description and link to the image while I'm at it:
document.getElementById("imageLink").setAttribute('href',imageArray[state][0])
document.getElementById('imageBoxText').innerHTML = imageArray[state][1];
OK, so now what I need to do is write a function that can do this for multiple images, side by side, reading from a modified imageArray that looks like:
imageArray = {'questionOne': [['www.linktoimage1.com,'Legend for image1'],['www.linktoimage2.com,'Legend for image2']]}
The code should be able to handle up to three images, but I certainly wouldn't mind if it could do any more.
I tried to do it using a table to represent the images and used a for loop with the code from earlier. The image would never load, stuck on the spinner for ever and the images would all bunch up on one side of the screen.
Any help appreciated, thanks very much.

Well, I think I see what you're trying to do.
It sounds like you're trying to make a slideshow of some kind.
This is an example of how I would have done it.
Here's the jsfiddle so you can see what's going on. http://jsfiddle.net/VodkaTonic/4KWLr/
(function () {
var imageArray = {
link: [['http://i.imgur.com/7OfqRbF.jpg', 'http://i.imgur.com/AHbc6zO.jpg','http://i.imgur.com/gW144OQ.jpg'],['http://i.imgur.com/v0V8hrB.jpg', 'http://i.imgur.com/9l40vIT.png','http://i.imgur.com/ZXYUttz.png']],
label: [['Legend for image1','Legend for image2', 'Legend for image3'],['Legend for image4','Legend for image5', 'Legend for image6']]
},
doc = document,
question = 0,
img = doc.getElementsByClassName('images'),
links = doc.getElementsByClassName('links'),
label = doc.getElementsByClassName('label'),
button = doc.getElementById('button');
function add (state) {
var arr = imageArray.link[state],
arr2 = imageArray.label[state];
arr.forEach(function(value,index,array) {
img[index]['src'] = value;
links[index]['href'] = value;
});
arr2.forEach(function(value,index,array) {
label[index]['innerHTML'] = value;
});
question++;
}
window.addEventListener('load', add(question), false);
button.addEventListener('click', function () {
add(question);
}, false)
}());

How to check {{message}} == "sometext" to display certain image

I have been looking into how to implement django to code to check {{message}} == "sometext" for my code. Currently there is an input to type in text on one page which display one another but I am having problems to get the input of the user to match a certain image to display on another page.
$(document).ready(function(){
var img = document.createElement("img");
img.src = "images/150.png";
var img2 = document.createElement("img2");
img2.src = "images/005.png";
var img2 = document.createElement("img2");
img2.src = "images/005.png";
var img3 = document.createElement("img3");
img3.src = "images/008.png";
if({{message.get()}}== "Mewtwo"){
var src = document.getElementById("image1");
src.appendChild(img);
if({{message.get()}}== "Charmeleon"){
var src = document.getElementById("image1");
src.appendChild(img2);
if({{message.get()}}== "Warturtle"){
var src = document.getElementById("image1");
src.appendChild(img3);
} })
Can someone offer advice on how this could be approached?

You are not quoting the message value here, you are generating text like if(Warturtle=="Warturtle"){.
You'll need to apply quoting, but to do so sanely I recommend you use JSON; that format is a subset of JavaScript and produces valid JavaScript literals.
You'll need to do so in your view (using json.dumps()), or you could use this Django snippet and do it straight in the template (no need to call serializers.serialize in the annotate method):
if({{message.get()|jsonify}} =="Warturtle"){

Javascript will not load the pictures

I want to load these banner.png files to the screen but all it prints out is the actual text from the banner array?
function randImg(){
var banner = new Array();
banner[0] = 'banner1.png';
banner[1] = 'banner2.png';
banner[2] = 'banner3.png';
maxImg = banner.length;
randNum = Math.floor(Math.random()*maxImg);
return banner[randNum];
}
any thoughts? I think I need to some how add a src but I am not sure how.

Might be too obvious, but...
function randImg(){
var banner = new Array();
banner[0] = 'banner1.png';
banner[1] = 'banner2.png';
banner[2] = 'banner3.png';
maxImg = banner.length;
randNum = Math.floor(Math.random()*maxImg);
return '<img src="' + banner[randNum] + '" />';
}
Demo: http://jsfiddle.net/AlienWebguy/u7yfq/

My pure javascript DOM manipulation is a little fuzzy (usually use jquery) but something like this should do the trick:
<div id="images"></div>
<script type="text/javascript">
function randImg(){
var banner = new Array();
banner[0] = 'banner1.png';
banner[1] = 'banner2.png';
banner[2] = 'banner3.png';
maxImg = banner.length;
randNum = Math.floor(Math.random()*maxImg);
var container = document.getElementById('images');
var img = document.createElement('img');
img.setAttribute('src',banner[randNum]);
container.appendChild(img);
}
</script>

The instruction that loads the image should be like this.
Where imgElement is an IMG element.
imgElement.src = randImg();
If you don’t know how to get an IMG element. Give the IMG element an ID attribute and load this like this.
For an IMG element as <img id="myImage" src="" />
Then:
var imgElement = document.getElementById("myImage");
imgElement.src = randImg();
Note.- my answer gives instruction on how to change the source of an IMG element that exists in the DOM (It is recommended to do so). You should NEVER document.write() an element, Neither on demand or when page is loading. That practice has been deprecated and many browsers would delete the whole page contents if you do so.