I am writing a custom TagHelper that should change its behavior based on what child elements its owner tag has. This will be used for substituting custom html elements in a localized string.
Here's a simple example of what I'm trying to do:
<h2 locale-key="Hello, %1!">
<span class="bold" locale-parameter="1">#userName</span>
</h2>
In the example above, the TagHelper for LocaleKey will change the content of the <h2> tag to a localized string. If this is a simple string with no parameters, then I can just simply use output.Content.SetHtmlContent() in the TagHelper to set the h2's content to the string. However in this case, the localized string has a parameter (%1), and I want the corresponding child element (<span parameter="1">) to be substituted in the final output. So the final rendered html would look like this:
<h2>Hello, <span class="bold">Lázár Zsolt</span>!<h2/>
To achieve this, I should be able to see all the child elements in the DOM from the LocaleKey TagHelper, so I can generate the correct HTML code. In the TagHelper's ProcessAsync method I can access the TagHelperContext and the TagHelperOutput, but I couldn't find any information about child elements in either of these objects while debugging. Is this possible somehow?
Another approach is to leave the string as is, with the %1 parameter key, and then use the child ParameterTagHelper to substitute itself into the parameterized string. To do this, I'd have to see the siblings of the current tag from the TagHelper.
Recursion would also be fun (e.g. the <span> is also localized and has its own parameters), but for the scope of this question, I'd be happy if I could get this to work without recursion.
I posted too soon again... There is a GetChildContentAsync() method in TagHelperOutput that will... get the child content asynchronously.
Related
Is it possible to conditionally add an attribute to an element using binding syntax? I am aware of if.bind, but that targets elements. Rather I am interested in targeting a specific attribute on an element.
Example:
<a href.bind="model.link">${model.text}</a>
If model.link is falsy, then I don't want the href at all--just treat the <a /> as a container element.
I realize I could create two <a /> tags--one with the attribute and one without--and use an if.bind on both, but that seem clunky and un-aurelia like.
I don't think it's supported in Aurelia currently (issue 1, issue 2)
This,
<a href.bind="addLink ? link : ''">Link</a>.
will produce
<a href>Link</a>
if addLink is false.
It won't remove the attribute entirely. If you are using a library which will check the existence of an attribute to manipulate the element, then this won't work. Another option would be to create a custom attribute like this. But that seems like an overhead.
I need get string inside slot before that slot is compiled. Is posibble?
Example
<div>
<slot>
<component-test text="test1"></component-test>
</slot>
</div>
I need as result "<component-test text="test1"></component-test>"
hmm seems its treating slot content html so .. in end result if you need it as string and use later on then you have to do some trick.
first you need to put real string there:
escape('<component-test text="test1"></component-test>');
output : %3Ccomponent-test%20text%3D%22test1%22%3E%3C/component-test%3E
use this output content and put that in slot.
this will treat as string.
now if you need to use that string's real html
convert it back to html using :
unescape('%3Ccomponent-test%20text%3D%22test1%22%3E%3C/component-test%3E')
output :
<component-test text="test1"></component-test>
in this way when you need to transfer html/string you can make it real string then when you need to use/compile make it html again.
Is there any reason why a repeat.for binding would remove attributes from elements inside the repeater?
<div repeat.for="i of model.someArray.length">
<label>Some Array - Index ${i + 1}</label>
<input value.bind="model.someArray[i]" some-custom-attribute="someArray[${i}]"/>
</div>
and that some-custom-attribute is not being output within the repeat, but if I were to remove the string interpolation within there then it outputs fine.
== Edit ==
I have put it in a comment but just to make sure everyone is on the same page, ideally this is the output I expect:
<input value.bind="model.someArray[i]" some-custom-attribute="someArray[0]"/>
The some-custom-attribute is not an aurelia attribute, its pure HTML that a 3rd party JS library uses, so the goal here is to get the textual value of the index into the textual attribute value.
model.someArray.length is a number, not an array. You need to iterate over the array. If you do need the current index, the repeater provides the $index property for you to use.
Your code should look like this:
<div repeat.for="item of model.someArray">
<label>Some Array - Index ${$index + 1}</label>
<input value.bind="item" some-custom-attribute.bind="item"/>
</div>
To answer your original question, doing some-custom-attribute="model.someArray[${i}]" makes Aurelia think you are trying to pass a string value to the custom attribute. You can see that in the following gist: https://gist.run/?id=eed8ac8623ff4749aa5bb93c82a7b1fb I've created a custom element that just pushes whatever value it is given in to an element on the page. Note!!! Don't ever do what I'm doing here! I just did this this way so you wouldn't have to open the js console. To actually get a value passed in, you would need to use some-custom-attribute.bind="item" or (to do things how you are doing things, some-custom-attribute.bind="someArray[i]"
I have this code for xpath and html:
<a class="WatchButton inicon" rel="nofollow" data-productid="111124">
xpath=/html/body/div[2]/div[2]/div/div[2]/div[1]/div[1]/div[2]/div[8]/a
How can I get the data-productid value?
Just add #data-productid to the xpath expression:
/html/body/div[2]/div[2]/div/div[2]/div[1]/div[1]/div[2]/div[8]/a/#data-productid
Note that the xpath expression you have is very fragile since it depends on a bunch of elements and their relevant positions. Try to rely on the element's attributes or one of it's containers - look for id and class attributes. For example:
//a[contains(#class, "WatchButton")]/#data-productid
This gets the first link anywhere on a page that contains WatchButton class and retrieves it's data-productid attribute value.
* Sharing the link to the web page or showing the complete HTML could help to provide you with a more reliable xpath expression.
If your prepend a FORM element with a P element, elements below the DIV in the example will not be selected!
<P><FORM id=f ...
<INPUT ...>
<DIV><INPUT (this element is not selectable)
</DIV>
</FORM>
No $('#f INPUT').events will happen in IE for the second input above
Try the testcase at: http://jsfiddle.net/jorese/Bzc7M/
In IE you will receive an alert=3, remove the P element in front of the FORM element and you get the expected alert=5. In Chrome|FF you get alert=5 as expected.
Can somebody explain this?
Your HTML code is not valid, it contains a few errors, the reason why some browsers render it is that they tolerate invalid code to some extent by trying to guess what the developer originally wanted to write.
The div element can be used to group almost any elements together. Indeed, it can contain almost any other element, unlike p, which can only contain inline elements.
Use div instead:
http://jsfiddle.net/mshMX/
Sitepoint reference: http://reference.sitepoint.com/html/p
W3 reference http://www.w3.org/TR/html4/sgml/dtd.html
A former StackOverflow question about the same problem: Why <p> tag can't contain <div> tag inside it?