Problem
I have a collection of images with linked captions on a page. I want them each to have identical HTML.
Typically, i copy and paste the HTML over and over for each item. The problem is, if i want to tweak the HTML, i have to do it for all of them. It's time-consuming, and there's risk of mistakes.
Quick and Dirty Templating
I'd like to write just one copy of the HTML, list the content items as plain text, and on page-render the HTML would get automatically repeated for each content-item.
HTML
<p><img src=IMAGE-URL>
<br>
<a target='_blank' href=LINK-URL>CAPTION</a></p>
Content List
IMAGE-URL, LINK-URL, CAPTION
/data/khang.jpg, https://khangssite.com, Khang Le
/data/sam.jpg, https://samssite.com, Sam Smith
/data/joy.jpg, https://joyssite.com, Joy Jones
/data/sue.jpg, https://suessite.com, Sue Sneed
/data/dog.jpg, https://dogssite.com, Brown Dog
/data/cat.jpg, https://catssite.com, Black Cat
Single Item
Ideally, i could put the plain-text content for a single item anywhere on a page, with some kind of identifier to indicate which HTML template to use (similar to classes with CSS).
TEMPLATE=MyTemplate1, IMAGE-URL=khang.jpg, LINK-URL=https://khangssite.com, CAPTION=Khang Le
Implementation
Templating systems are widely used, like Django and Smarty on the server side, and Mustache on the client side. This question seeks a simple, single-file template solution, without using external libs.
I want to achieve this without a framework, library, etc. I'd like to put the HTML and content-list in the same .html file.
Definitely no database. It should be quick and simple to set it up within a page, without installing or configuring additional services.
Ideally, i'd like to do this without javascript, but that's not a strict requirement. If there's javascript, it should be ignorant of the fieldnames. Ideally, very short and simple. No jquery please.
you mean Template literals (Template strings) ?
const arrData =
[ { img: '/data/khang.jpg', link: 'https://khangssite.com', txt: 'Khang Le' }
, { img: '/data/sam.jpg', link: 'https://samssite.com', txt: 'Sam Smith' }
, { img: '/data/joy.jpg', link: 'https://joyssite.com', txt: 'Joy Jones' }
, { img: '/data/sue.jpg', link: 'https://suessite.com', txt: 'Sue Sneed' }
, { img: '/data/dog.jpg', link: 'https://dogssite.com', txt: 'Brown Dog' }
, { img: '/data/cat.jpg', link: 'https://catssite.com', txt: 'Black Cat' }
]
const myObj = document.querySelector('#my-div')
arrData.forEach(({ img, link, txt }) =>
{
myObj.innerHTML += `
<p>
<img src="${img}">
<br>
<a target='_blank' href="${link}">${txt}</a>
</p>`
});
<div id="my-div"></div>
This answer is a complete solution. It's exciting to edit the HTML template in codepen and watch the layout of each copy change in real time -- similar to the experience of editing a CSS class and watching the live changes.
Here's the code, followed by explanation.
HTML
<span id="template-container"></span>
<div hidden id="template-data">
IMG,, LINK,, CAPTION
https://www.referenseo.com/wp-content/uploads/2019/03/image-attractive.jpg,, khangssite.com,, Khang Le
https://i.redd.it/jeuusd992wd41.jpg,, suessite.com,, Sue Sneed
https://picsum.photos/536/354,, catssite.com,, Black Cat
</div>
<template id="art-template">
<span class="art-item">
<p>
<a href="${LINK}" target="_blank">
<img src="${IMG}" alt="" />
<br>
${CAPTION}
</a>
</p>
</span>
</template>
Javascript
window.onload = function LoadTemplate() {
// get template data.
let sRawData = document.querySelector("#template-data").innerHTML.trim();
// load header and data into arrays
const headersEnd = sRawData.indexOf("\n");
const headers = sRawData.slice(0, headersEnd).split(",,");
const aRows = sRawData.slice(headersEnd).trim().split("\n");
const data = aRows.map((element) => {
return element.split(",,");
});
// grab template and container
const templateHtml = document.querySelector("template").innerHTML;
const container = document.querySelector("#template-container");
// make html for each record
data.forEach((row) => {
let workingCopy = templateHtml;
// load current record into template
headers.forEach((header, column) => {
let value = row[column].trim();
let placeholder = `\$\{${header.trim()}\}`;
workingCopy = workingCopy.replaceAll(placeholder, value);
});
// append template to page, and loop to next record
container.innerHTML += workingCopy;
});
};
New version on github:
https://github.com/johnaweiss/HTML-Micro-Templating
Requirement
As specified in the question, this solution is intended to optimize the coding experience on the HTML side. That's the whole point of any web templating. Therefore, the JS has to work a little harder to make life easier for the HTML programmer.
The question seeks a reusable solution. Therefore, JS should be ignorant of the template, fields, and data-list. So unlike #MisterJojo's answer, the template and all data are in my HTML, not javascript. The JS code is generic.
Design
My solution is based on the <template> tag, which is intended for precisely this usage. It has various advantages, like the template isn't displayed, processed, or validated by the browser, so it has less impact on performance. Programmer doesn't have to write an explicit display:none style.
https://news.ycombinator.com/item?id=33089975
However, <template> tags are normally only intended for loading content into the layout. That's inadequate. This tool allows template variables anywhere in the HTML, including inside the tags (eg attributes like <img src).
HTML
My HTML has three blocks:
template: The HTML coder develops their desired display-structure of the output, in real HTML (not plain text). Uses <template>
data: The list of records each of which should be rendered using the same template. Uses <span> with a HIDDEN attribute.
container: The place to display all the output blocks. Uses <span>.
Template
My sample template includes 3 placeholders for data:
${LINK}
${IMG}
${CAPTION}
But of course you can use any placeholders, any number of them. I use string-literal delimiting-style (although i'm not actually using them as string-literals -- i just borrowed the delimiter style.)
Data Element
The question specifies data should be stored in HTML. It should require minimal keystrokes.
I didn't want to redundantly retype the fieldnames on every row. I didn't use slotting, JSO, Jason, or XML syntax, because those are all verbose.
https://developer.mozilla.org/en-US/docs/Web/Web_Components/Using_templates_and_slots
It's a simple delimited list. I eliminated all braces, brackets, equals, parens, colons etc.
I put the fieldname-headers only on the first row. The headers are a visual aid for the HTML developer, and a key for Javascript to know the fieldnames and order.
Record Delimiter: End-of-line
Field Delimiter: Double-commas. Seems safe, and they're easy to type. I don't expect to see double-commas in any actual data. Beware, the developer must enter a space for any empty cells, to prevent unintended double-commas. The programmer can easily use a different delimiter if they prefer, as long as they update the Javascript. You can use single-commas if you're sure there will be no embedded commas within a cell.
The data block is hidden using the hidden attribute. No CSS needed.
It's a span to ensure it takes up no room on the page.
JAVASCRIPT
Data
The data is processed by Javascript with two split statements, first on newline delimiter, then on the double-comma delimiter. That puts the whole thing into a 2D array. My JS uses trims to get rid of extra whitespace as needed.
Place-holder Substitution
Handling multiple entries requires plugging each entry into the template.
i went with simple string-replacement instead of string literals.
Multiple Templates
New version which supports multiple templates, and ability to use same template in multiple locations on same page.
https://github.com/johnaweiss/HTML-Micro-Templating
Future
Inspired by #MisterJojo, an earlier version of my solution used template literals to do the substitution. However, that was a bit more complicated and verbose, and seemed to require use of eval. So i switched to .replaceAll. Yet template-literals seems like a more appropriate method for templates, so maybe i'll revisit that.
A future version may adapt to whatever custom field-delimiter the HTML developer uses for the data block.
The dollar-curly delimiter for placeholders is a bit awkward to type. So i'm interested in finding a less awkward non-alpha delimiter that won't conflict with HTML. Considering double-brackets or braces [[NAME]]
Maybe there are simpler ways to pull the data-table into JS.
I've read components work well with <template>, but i didn't go there.
Imo, the JS committee should develop a variable-placeholder feature for <template> tags, and natively accommodate storing the data in HTML. It would be great if something like this solution was part of the rendering engine.
I was wondering if it was possible to highlight code written using the HTML <code>...</code> tags in a similar fashion to the native markdown code block using the tripe backtick ```.
I prefer the <code>...</code> environment due to its ability to be customized using css, as I want code to stand out visually.
You can customise the styles of the code syntax-highlighted by triple backtick by wrapping it in a <div>:
<div style="font-weight: bold">
```javascript
var x = 1;
function y() {
return 0;
}
```
</div>
Note the extra new lines (otherwise it will not render properly). This works well in JupyterLab:
JupyterLab jupytext
This extension adds a few Jupytext commands to the command palette. You can use it to select the desired ipynb/text pairing for your notebook.
var bannerText = stringFormat("This is my {0}test content{1} here", "<b>", "</b>");
<div>
<p> {para1}</p>
<p> {bannerText}</p>
</div>
html tags gets printed instead of applying them as text
Observed output
This is my <b>test content</b> here
Needed output
This is my test content here
<div [innerHTML]="bannerText"></div>
However, keep in mind Angular's docs about security, which says Angular recognizes the value as unsafe and automatically sanitizes it, which removes the <script> tag but keeps safe content such as the <b> element..
check the below code it might help you.use innerHtml
document.getElementById("name").innerHTML="This is <u>my test</u> sample"
<div id="name"></div>
.
Observed output This is my <u>test content</u> here
Whatever method you are using is escaping the html e.g. < / > etc.
Fix
You need some version of set HTML.
e.g. React : dangerouslySetInnerHTML, Pure JS: Use innerHTML
Warning
Be careful, setting html exposes your app to XSS : https://en.wikipedia.org/wiki/Cross-site_scripting
I am assisting on a project right now and building out templates for the first time, trying to wrap my head around a few things but one aspect of the html that's confusing me are certain things sitting in square brackets. I've never used these in html before so I'm just wondering what they are for (when I open the page in a browser they all show up as text)
Here's a bit of the code:
<div class="container">
[HASBREADCRUMBS]
<ol class="nav-breadcrumb">
[BREADCRUMBS]
</ol>
[/HASBREADCRUMBS]
<h1 class="header-title" style="color:[TITLECOLOR];font-size:[TITLESIZE];">[TITLE]</h1>
</div>
It's using some templating engine and the whole page is parsed before getting output to the browser. During parsing, those square bracket tags work as something else (depending on the templating engine used).
So, for example, [HASBREADCRUMBS] and [/HASBREADCRUMBS] could denote a piece of code that might be similar to:
if (breadcrumbs) {
and:
} // closed if
and for each value of the breadcrumbs object (whatever it might be) one ordered HTML list is rendered with the breadcrumb value as its content ([BREADCRUMBS]).
So in short: it's not HTML, that part of the file never reaches the browser but is converted into proper HTML (based on conditions, can also use loops, etc.) before rendering.
The square brackets have nothing to do with HTML. They probably belong to the template and will be replaced by actual value from the template engine.
This question already has answers here:
How to display raw HTML code on an HTML page
(30 answers)
Closed 3 years ago.
I'd like to add an area to a page where all of the dynamic content is rendered as plain text instead of markup. For example:
<myMagicTag>
<b>Hello</b> World
</myMagicTag>
I want the <b> tag to show up as just text and not as a bold directive. I'd rather not have to write the code to convert every "<" to an "<".
I know that <textarea> will do it, but it has other undesirable side effects like adding scroll bars.
Does myMagicTag exist?
Edit: A jQuery or javascript function that does this would also be ok. Can't do it server-side, unfortunately.
You can do this with the script element (bolded by me):
The script element allows authors to include dynamic script and data blocks in their documents.
Example:
<script type="text/plain">
This content has the media type plain/text, so characters reserved in HTML have no special meaning here: <div> ← this will be displayed.
</script>
(Note that the allowed content of the script element is restricted, e.g. you can’t have </script> as text content (it would close the script element).)
Typically, script elements have display:none by default in browser’s CSS, so you’d need to overwrite that in your CSS, e.g.:
script[type="text/plain"] {display:block;}
You can use a function to escape the < >, eg:
'span.name': function(){
return this.name.replace(/</g, '<').replace(/>/g, '>');
}
Also take a look at <plaintext></plaintext>. I haven't used it myself but it is known to render everything that follows as plain text(by everything i mean to say it ignores the closing tag, so all the following code is rendered as text)
The tag used to be <XMP> but in HTML 4 it was already deprecated. Browser's don't seem to have dropped its support but I would not recommend it for anything beyond quick debugging. The MDN article about <XMP> lists two other tags, <plaintext> and <listing>, that were deprecated even earlier. I'm not aware of any current alternative.
Whatever, the code to encode plain text into HTML is pretty straightforward in most programming languages.
Note: the term similar means exactly that—all three are designed to inject plain text into HTML. I'm not implying that they are synonyms or that they behave identically—they don't.
There is no specific tag except the deprecated <xmp>.
But a script tag is allowed to store unformatted data.
Here is the only solution so far showing dynamic content, as you wanted.
Run code snippet for more info.
<script id="myMagicTag" type="text/plain" style="display:block;">
<b>Hello</b> World
</script>
Use Visible Data-blocks
<script>
document.querySelector("#myMagicTag").innerHTML = "<b>Unformatted</b> dynamic content"
</script>
No, that's not possible, you need to HtmlEncode it.
If your using a server-side language, that's not really difficult though.
In .NET you would do something like this:
string encodedtext = HttpContext.Current.Server.HtmlEncode(plaintext);
In my application, I need to prevent HTML from rendering
"if (a<b || c>100) ..."
and
"cout << ...".
Also the entire C++ code region HTML must pass through the GCC compiler with the desired effect. I've hit on two schemes:
First:
//<xmp>
#include <string>
//</xmp>}
For reasons that escape me, the <xmp> tag is deprecated. I find (2016-01-09) that Chrome and FF, at least, render the tag the way I want. While researching my problem, I saw a remark that <xmp> is required in HTML 5.
Second, in <head> ... </head>, insert:
<style type="text/css">
textarea { border: none; }
</style>
Then in <body> ... </body>, write:
//<br /> <textarea rows="4" disabled cols="80">
#include <stdlib.h>
#include <iostream>
#include <string>
//</textarea> <br />
Note: Set "cols="80" to prevent following text from appearing on the right. Set "rows=..." to one more line than you enclose in the tag. This prevents scroll bars. This second technique has several disadvantages:
The "disabled" attribute shades the region
Incomprehensible, complex comments in the code sent to the compiler
Harder to understand
More typing
However, this methhod is neither obsolete nor deprecated. The gods of HTML will make their faces to shine unto you.