I've created a RDFa snippet to use on a client's website using the GoodRelations tool. The generated code creates the tags as expected, but there's no text between the divs, for instance:
<div typeof="vcard:Address">
<div property="vcard:locality" content="Yorba Linda"></div>
</div>
I'm assuming that this is OK, and that I am expected to put descriptive text for humans between the 'locality' divs without any adverse effects (in relation to SEO.) Correct?
As William says: In most cases, is is impractical to reuse visible content for publishing meta-data, because they differ in sequence or structure. In that case, it is better to put all meta-data in a single block of <div> elements without visible content. This is called "RDFa in Snippet Style", see
http://www.ebusiness-unibw.org/tools/rdf2rdfa/
Hepp, Martin; García, Roberto; Radinger, Andreas: RDF2RDFa: Turning RDF into Snippets for Copy-and-Paste, Technical Report TR-2009-01, 2009., PDF at http://www.heppnetz.de/files/RDF2RDFa-TR.pdf
Google is consuming such markup, despite a general preference for marking up visible content. Many big shops are using this approach with good results, e.g. http://www.rachaelraystore.com/Product/detail/Rachael-Ray-Stoneware-2-pc-Bubble-Brown-Baker-Set-Eggplant/316398
So if you can integrate the visible content and the RDFa constructs, then use
<div typeof="vcard:Address">
<div property="vcard:locality">Yorba Linda</div>
</div>
If you cannot, then use
<div typeof="vcard:Address">
<div property="vcard:locality" content="Yorba Linda"></div>
</div>
...
<div>
<div>Yorba Linda</div>
</div>
But the divs with invisible content must be close to the visible content and be placed better before than after the visible markup.
From and RDFa point of view, it is fine (I am assuming you are using bracers because you don't know how to escape greater than / less than characters).
The only thing you need to think about is how adding this fragment of HTML to your HTML document, will affect the rendering. Based on the fact that you are using the content attribute, this fragment is destined to remain hidden. So yo should think about this in relation to the CSS architecture. My advice would be to create a specific CSS class that is for annotations.
Having spoken to the author of Good Relations, his advice would be to put this fragment before any other HTML element in the body of your document. Generally, the Rich Snippets team indicate that they ignore hidden RDFa, but it doesn't actually matter and really in the long run it enables the publishing of RDF to anyone (not only Google) who wants to consume it.
Related
I just come across a good write up for a new ASP.NET Core feature called Tag helpers.
From there, I understood that one can replace the following code:
#model MyProject.Models.Product
#using (Html.BeginForm())
{
<div>
#Html.LabelFor(m => p.Name, "Name:")
#Html.TextBoxFor(m => p.Name)
</div>
<input type="submit" value="Create" />
}
with:
#model MyProject.Models.Product
#addtaghelper "Microsoft.AspNet.Mvc.TagHelpers"
<form asp-controller="Products" asp-action="Create" method="post">
<div>
<label asp-for="Name">Name:</label>
<input asp-for="Name" />
</div>
<input type="submit" value="Save" />
</form>
There's some new syntax such as asp-controller, asp-for, etc. But what does it do? And what's the advantage of this new approach?
The most important improvement I've seen so far is the control it guarantees over your HTML elements. While convenient, the Html helpers used by MVC create problems when you try to do things they weren't built for.
A simple example can be seen when using the TextBox in MVC5:
#Html.TextBoxFor(m => p.Name)
The resulting HTML markup looks like:
<input class="form-control" id="Name" name="Name" type="text" value="">
Nice and simple. But what if you want to add a placeholder attribute? What if you want to use bootstrap's validation states? What if you have some 3rd party super cool javascript library which needs custom attributes. None of these things were possible in the initial release of MVC5. Though they were eventually added via update in the form of htmlAttributes. Even now adding custom attributes is kludgey at best.
#Html.TextBoxFor(m => p.Name,
new {#class="form-control has-error", placeholder="Enter Name",
superCoolFeature="Do something cool"})
While you could argue this is still less code that straight HTML, it is no longer a significant advantage. Worse, this solution still doesn't cover dashes in attributes which are fairly common. If you need them you are stuck with a workaround such as ActionLink htmlAttributes
I've gone down the route of fixing these deficiencies with custom editors, and tried building my own TextBox controls. It became obvious pretty quickly that replacing the included TextBox templates would require a lot of work. Worse, your templates have to have knowledge of any extensions you are adding to use them.
It seems like the inclusion of Bootstrap and other 3rd party tools into MVC have made it more obvious that the current design has problems with extending HTML which need to be fixed. Hopefully the tag helpers implementation is complete enough that we can avoid them in the future.
Not to mention, your Web Designers will have real HTML tags to edit that they recognize to re-design your pages. Designers shouldn't have to be coders and there's enough for these sharp folks to keep up with, studying the moving targets of HTML5 and CSS3 specs.
A few things come to mind:
As #ChrisWalter points out, these tag helpers give HTML tags an Open/Closed quality. Rather than just letting you write extension methods for common HTML patterns, you can extend an HTML element. This lets you pick-and-mix multiple extensions per component, rather than having to choose between them.
HTML Helpers tend to not work super well for elements that need to have inner HTML provided as an argument. They came up with a clever pattern so you can say:
#using (Html.BeginForm(...)){
{
<input ... />
}
But there's nothing about BeginForm() that would force you to put it in a using statement, and there's nothing to prevent you from using incorrect HTML structure. (<input> technically isn't allowed to be directly inside a <form> tag.)
This gives us a really easy transitional stepping stone into the Web Components world of HTML5. A component that you write today for jQuery or Bootstrap to pick up and enhance may make more sense as an Angular 2 or Polymer component in a few years. Using HTML syntax makes it possible to write your HTML the way you want it to look when it's a web component, and have it automatically translated into the structure it has to take on for now (or for specific browsers, later).
Accepted answer is correct but just a correction.
Html Helpers cover dashes in attributes by use of underscore. for example if you want html like
my-attr=value
then you can use html helpers like
#Html.TextBoxFor(m=>m.id,
new { my_attr = value })
then it will convert accordingly.
I know the original question asks about advantages but for the sake of completeness I have to mention one disadvantage:
With tag-helpers enabled you cannot inject C# code inside tag attributes.
I.e. this code will break:
<!-- this won't work -->
<input class="#GetMyClass()">
<!-- this won't work too -->
<input type="checkbox" #(condition ? "checked" : "") >
To work around this problem you can use custom tag helpers or just disable tag helpers altogether like described in this answer: https://stackoverflow.com/a/65281018/56621
P.S. My humble opinion that can be safely ignored: tag helpers are "magic". And "magic" is always bad in programming. If something looks like an HTML tag, walks like a tag and quacks like a tag - then it should probably be an HTML tag. Without me knowning "oh, it's not *really* a tag".
From building a basic web app from the ground up in .NET 7/Razor pages, I haven't encountered a single instance where a tag helper has an advantage over simply coding the HTML. I don't come from an MVC background so maybe that is where the advantage lies but as seen before...Microsoft has released yet another version of wheel-reinvention that instead of making things easier for some simply adds more confusion to others.
We have several forms in our application which have made extensive use of widgets.
Unfortunately, this causes the form to load in a very "jittery" manner. It still loads pretty quickly, but you can perceptively see each widget 'pop' into view one-by-one.
Is this an expected side affect of the widget infrastructure, or is there a technique whereby we can coerce Durandal into constructing the entire view (widgets and all) before attaching, which seems to be how partial views work? (We were able to convert many of these widgets into partial views to mitigate the phenomenon).
How to easily reproduce the behavior
Using the HTML samples, find app/widgets/index.html and make a small modification to create a view which will have lots of widgets:
<div>
<h1>Widgets Sample</h1>
<!-- ko foreach: new Array(100) -->
<div data-bind="expander:{items:$root.projects}">
<h3 data-part="header">Project: <span data-bind="text: name"></span></h3>
</div>
<!-- /ko -->
<button class="btn" data-bind="click: addNewProject">Add</button>
</div>
When refreshing the page, you will see the scrollbar "shrinking down" visibly. I suspect this is because each individual widget is being added to the DOM one at a time, rather than "all at once with the parent view" which is how partial views work.
Note: The affect is fairly subtle with this very simple markup, but the more complicated the UI elements, the more noticeable and jarring the "studdering" becomes (especially when you have non-widget content nested in between various wisgets).
Looks like there's no obviouse answer at the moment, but there's an issue at https://github.com/BlueSpire/Durandal/issues/434 that is cross linked with this questions.
I generate html documents that contain a menu and a content part. Then I want to extract the content of these document to feed it to a lucene index. However, I would like to exclude the menu from the content extraction and thus only index the content.
<div class="menu">my menu goes here</div>
<div class="content">my content goes here</div>
what is the simplest way to achieve this with apache tika?
As a more general solution (not just for you specific menu) I would advise looking at boilerpipe that deals with removing uninteresting parts from pages (menus, navigation etc).
I know it can be integrated in Solr/tika, have a look and you probably can integrate it in your scenario.
Have a look at this post which specifies how to handle DIVs during the HTML parse, by specifying whether they are safe to parse or not, in which case its ignored. For your problem, you could have some logic in the override methods which ignore only DIV elements with attribute value "menu" (i.e. tell TIKA parser this DIV is unsafe to parse).
You can parse the html with a parser to a xhtml dom object an remove the div tag cotaining the attribute class="menu".
To embed microdata that should be hidden or isn't provided as text you can use meta elements. Here is an example for non-visible properties using meta elements. Is there a similar way to hide instances of types?
For example I have a page with a table that lists events of a single performer. The performer is implicit and is not repeatedly shown for every entry, so I hide it in a meta element. The performer property should be of the type Person, which has additional attributes that I also want to hide. I'm trying to achieve something like this:
<meta itemprop="performer" itemscope itemtype="http://schema.org/Person">
<meta itemprop="name" content="Some performer"/>
</meta >
Of course this won't work, the meta element must be empty. Using other elements and hiding them with CSS would work but probably isn't very nice for screen readers. Is there any recommended way to do this?
In this case the person scope could be a <span> tag? That tag has no semantic value and if there are only meta tags inside it, it shouldn't be visible in your site.
You could also look into itemref and add the Person only once to the page and reference that id multiple times. However not all testing tools support itemref, so testing if it's correctly set up is quite hard at the moment.
I am new to HTML5 and am wondering which HTML5 tag should be used on a Call to Action div that sits in a column next to the main content on the home page.
Option 1:
<aside>
//call to action
</aside>
Option 2:
<article>
<section>
//call to action
</section>
</article>
The reason I ask is because I don't see either option as being a perfect fit. Perhaps I am missing something. Thanks!
My HTML for the Call to Action:
<section class="box">
<hgroup>
<h1 class="side">Call Now</h1>
<h2 class="side">To Schedule a Free Pick-Up!</h2>
<ul class="center">
<li>Cleaning</li>
<li>Repair</li>
<li>Appraisals</li>
</ul>
<h3 class="side no-bottom">(781) 729-2213</h3>
<h4 class="side no-top no-bottom">Ask for Bob!</h4>
</hgroup>
<img class="responsive" src="img/satisfaction-guarantee.png" alt="100% Satisfaction Guarantee">
<p class="side">We guarantee you will be thrilled with our services or your money back!</p>
</section>
This is a box on the right column of a three column layout. The content in the large middle column gives a summary of the company's services. If you wanted to use those services, you would have to schedule a pick-up, hence the call to action.
Does anyone object to this use of HTML5, or have a better way?
My take is that the best practices for the new HTML5 structural elements are still being worked out, and the forgiving nature of the new HTML5 economy means that you can establish the conventions that make the most sense for your application.
In my applications, I have separate considerations for markup that reflects the layout of the view (that is, the template that creates the overall consistency from page to page) versus the content itself (usually any function or query results that receive additional markup before being inserted into the various regions in the layout). The distinction matters because the layout element semantics (like header, footer, and aside) don't really help with differentiation of the content during search since that markup is usually repeated from page to page. I particularly favor using the semantic distinctions in HTML5 to describe the content the user is actually searching on. For example I generally use article to wrap the primary content and nav to wrap any associated list of links. Widget wrappers are usually tied to the page layout, so I'd go with the convention of the template for that guideline.
Whenever I have to decide on semantic vs generic names, my general heuristic is:
If there is a possible precedent already in the page template, follow that precedent;
If the element in question is new part of the page layout (vs a content query that is rendered into a region in the layout) and there is no guiding pattern in the template already, div is fine for associating that page layout behavior to;
If the content is created dynamically (that is, anything that gets instanced into the layout at request time--posts, navigation, most widgets), wrap it in a semantic wrapper that best describes what that item is (vs how you think it should appear)
Whenever authoring or generating content, use semantic HTML5 markup as appropriate within that content (hgroup to bracket hierarchical headings, section to organize chunks within the article, etc.). This is future-proof enrichment for search.
According to all this, div would be fine as a wrapper for your widget unless your page template already establishes a different widget wrapper. Also, your use of heading elements for creating large, bold appearance within the widget is using markup for appearance rather than for semantics. Since your particular usage is appearance-motivated, it would be better to use divs or spans with CSS classes that can let you specify sizes, spacing, and other adornments as needed for that non-specific text rather than having to override the browser defaults for the heading elements. I'd save the heading elements for the page heading, for widget headings, and for headings within the primary content region of the page. There can be SEO ranking issues for misuse of headings that are not part of the main content.
I hope these ideas help in your consideration of HTML5 markup usage.
So far as the semantics of the markup go, Don's advice makes sense. (As you said your CTA was visually beside the main content and secondary to that content, I would favor aside, but there's no single correct answer.)
However, you've tagged your question with "seo," so I take it you're interested in the SEO benefits of using the right markup. At this time, Google doesn't give special weight to having nice, semantic markup---they don't care about the difference between things like aside, section, and div. This may be partly because the meaning of these tags is still being defined (by the practice of Web devs), but they even seem to ignore tags that are clearly relevant search results (like nav, which will almost always be irrelevant to a page's description in the search results).
Instead, they heavily favor using microdata for marking up rich semantics. In the short term, marking your page up using the Schema.org WebPage microdata will likely provide greater benefit. You can mark your CTA as a relatedLink or significantLink, and keep it outside the mainContent of the page. If you're looking to optimize your page for search, this is a great way to do it---in my experience, Google very rarely shows text outside of your mainContent block in the search results description.
Proper markup depends on the actual content, which you have not provided.
That said, wrapping everything in a div is fine (although perhaps unnecessary) no matter what your content is as the <div> tag has no semantic value. Your two examples are probably not correct, unless your "call to action" is literally an entire article (which I doubt is the case).
The call to action might occur within an <aside>, but it's not likely that the call to action is the aside itself. Once again, that depends on the content (what it is) and context (where it is in relation to other content).
Typically "call to action" is a link somewhere, so the obvious answer to me is using an anchor, <a>.
It's just a link to another page. Use a div.