Develop Reference

Convert HTML entities inside <code> tag to display on web site?

Good day,
I'm writing some HTML/CSS code examples on a web site. I'm using the <code> element to mark out my examples.
I'm trying to:
Convert all HTML-tags inside my <code> blocks to be displayed on my web site
Make my examples beautiful with syntax highlighting and maybe even auto indent
I have tried PrismJS and Highlighter.JS but I cannot get any of them to convert the HTML tags. Are you forced to make it server side? And if so are there any PHP-examples or tools for this that works fine with any of the JS-libraries?
Thanks in advance

Well you might do a simple trick to display html and css codes without and tag
You might simply but the text inside a input within the code
Then you might simply style it and give it custom background and everything also it will be easy for the user to copy it but make sure to right the code you want to display inside the html code not on the rendered page or it will not be displayed to the users like this
<input type="text" name="html_test_code">whatever code here</input>
And then the styling of sytax might be done using js easily

How do I use small html markup repeatedly?

I am working on standalone JavaScript application which is being coded in HTML 5.
It has almost 50-60 html pages including repetitive markup such as header, footer and nav.
But if I have to make change in header then I have to make changes in 56-60 pages.
Is there any solution to use reusable html markup so if I did changes in one page it will reflect to other pages?
I can't even use php.

Prepare one javascript function. Write your html elements through javascript or jquery function. run it in page load event. and call the function in html by div.
Put this javascript function in separate .js file. And call this js file in wherever you want. And just place the div wherever you want in the html page.
See this jsfiddle DEMO
I Hope this demo will useful to you in this situation.

If you are using HTML (.html) pages and do not have Server-Side-Includes option then you can use a JavaScript template (which is not too difficult).
Second option : use of iframe.
Write the whole javascript code in common_layout.js
Add every statement using id of that div and add this file with main layout.
$( document ).ready(function() {
$('#header').html('<b>Header</b><ul><li>First Link</li><li>Second Link</li></ul> ');
});
UPDATE: One of my favorite post from TutsPlus : Best practices when working with JS Templates

If you are just started with this application. You can think of using client side java script frameworks like - AngularJS. It would be lot easier to maintain the code and solve such trivial issues.

You can use object tag like this:
<object name="header" type="text/html" data="header.html"></object>

Inserting Text Into HTML

What I Want: Very simply I have a C program that generates a variable periodically, I want to be able to display this value on a website.
Restrictions: The webpage is HTML, php does not work, javascript does [I have tried a few javascript solutions but they have all been long, tedious and in the end ineffective] I want it to be able to format the text so that it matches the rest of the webpage. Above all I'd really like to find something simple that works.
Freedoms: I can output the variable from my C program to just about any file type and content that I want, the file is hosted so is available locally to the server or online for the client.
Preferred Solutions: I am currently playing around with the object and iframe tags native to html. They give a nice simple input:
<object height=20 width=75 type='text/plain' border=0 data="URL/filename.txt"></object>
inserts the contents of my file, but it can't be formatted so I am stuck with 12pt Courier font which is not acceptable. Using
<iframe seamless height=20 width=75 scrolling='no' src="URL/filename.htm"></iframe>
and adding my desired font/colour/size etc to the htm file gets me the right text style, but htm has a large amount of white padding around it which I can't seem to get rid of so I have to make my iframe quite large for the text to be displayed, but then it doesn't fit smoothly with other text.
So anyone that can answer one of four questions:
How to remove excess padding from htm
How to format the style of a html object
Is there anything in Java as simple as the php [so apparently it doesn't show php code even when you quote it as code. But basically using echo and get_file_contents to insert the contents of a txt file into a html page]
Propose an alternate solution

Padding and style can be handled by css.
By java I assume you mean javascript - google-ing will help you. Without details of what your server is running and what is dispatching your pages we can't give you an exact answer. You might want something with ajax to keep it updating in the background.
Try googling your question, you'd be surprised how often this helps.

I'm not sure what you're trying to do once you get the variable into your web page, but I think something like the following could be useful.
Create a hidden div on your page
Have your C application write the variable to some file
Use jquery to execute an ajax call to pull that value into the div ( or whatever other container you want to use
using some type of timer, execute the ajax call every X period of time, which will then get your up to date variable
on your main page, have another timer that will then come in to that container, grab your value and then you are free to do what you want with it.
This is all off the top of my head without knowing much about what you're trying to accomplish. If you provide some further details we may be able to help you a little more.

You need AJAX... that's just a fancy buzz-word. It means you can tell JavaScript can get a file from the server without reloading the page and you can insert data from that file into your HTML.
AJAX is made much simpler by using a JavaScript library like jQuery, but it can be done without jQuery. There's a pretty decent Getting Started tutorial at Mozilla Developer Network if you want to do it the hard way, but I really recommend jQuery.
As far as formatting... any formatting... you need to use CSS. Just about everything about the appearance of anything on a web page is controlled by CSS. MDN has a Learn CSS section, too.

load jquery on you main html file
put a div with some id (example id="newvalue")
make you c program to write the output in a file (for example value.html)
on main html page header, after jquery include code add some javascript like
$( document ).ready(function() {
$("#newvalue").load('yoursiteurl/value.html');
});

View HTML of jQuery injected code

I'm thinking of using a couple jQuery tools/plugins to dynamically change the DOM of a page:
http://plugins.jquery.com/project/appendDom
http://www.botsko.net/blog/2009/04/07/jquery-form-builder-plugin/
When the new DOM is changed, I can use Firebug to see the new elements as they are added, but I'm wondering if anyone has suggestions on how I can also build an .html page that can be saved off after a number of elements have been added.
My ultimate goal is to create an HTML Form Builder that will generate the HTML output so I can save the work as I go along. I also want to take the output that was generated and upload it, have it parsed, which will allow me to continue working at another time.
Any thoughts on how to at least get the .html file would be great or tools that I can use.

Assuming that you will just be needing the bits inside the body tag of the page you can get the HTML with document.body.outerHTML.

You can use the native outerHTML:
vat thehtml = $('#yourElement')[0].outerHTML;

You could use jQuery to get the HTML of the entire <body> section:
$('body').html();

Can you insert a form onto a page using jQuery's $.load() function?

I have a page where there's a drag and drop table where the order of the rows determines the value of a subtotal. However, it's more complicated than just addition and I would rather not duplicate the logic in JavaScript to update the values.
A simple solution would be to reload the whole page using Ajax and then replace the table from the page fetched via Ajax. Perhaps it's not the most elegant solution but I thought it'd be a quick way to get the job done that would be acceptable for now.
You can do that with jQuery like this:
$('#element-around-table').load(document.location.href + ' #table-id');
However, my "simple" solution turned out to not be so simple because the table also contains a <form> tag which is not being displayed in Firefox (Safari works).
When I inspect the page using Firebug, I see the form, but it and its elements grayed out.
Searching on the web, I found a rather confused post by a guy who says FF3 and IE strip <form> tags from innerHTML calls.
I'm probably going to move on to do this some other way, but for my future reference, I'd like to know: is this the case?

That post is rather confused, I just tested your code and it worked fine. The form tag was shown in firefox 3.0.8 just fine.
Looking at you code example, though I wonder if you just gave an incomplete example... make sure that the page you call returns only the html that goes inside that wrapper element.

I've run into this type of thing before. FORM tags need to be added to the DOM. If they're added using a method that writes to innerHTML, the tag will appear, but it won't be there as far as JavaScript is concerned.