sc:FieldRenderer and EnclosingTag

If you have a piece of content that requires a surrounding tag (like ‘h2’ around a heading, or ‘p’ around the contents of a multi-line text field), you can use ‘EnclosingTag’ on the FieldRenderer control; it will not display the enclosing tag if the field is empty.

<sc:FieldRenderer FieldName="Heading" EnclosingTag="h2" runat="server" />

Produces:

<h2>My heading content</h2>

Strangely, it does not exist on the more specialised controls, like sc:Text or sc:Link.

7 Comments

  1. Mike Reynolds says:
    October 31, 2012 at 03:14

    I had no idea this attribute was available on the FieldRenderer Web Control.

    Since I didn’t know about this attribute, I ended up creating a custom Field Control that does just this, and blogged about it here: http://sitecorejunkie.com/2012/10/29/yes-you-too-can-build-a-custom-field-control/

    Thank you for sharing this!

    -Mike

    Reply
    1. Martina says:
      October 31, 2012 at 10:14

      Likewise; I only found out about it very recently.

      I’ve seen custom controls that use templates, so that you aren’t restricted in the amount of surrounding markup, e.g.:

      <custom:FieldRenderer Field="Heading" runat="server">
    <HeaderTemplate><h1 class="nostyle"><span></HeaderTemplate>
    <FooterTemplate></span></h1></FooterTemplate>
</custom:FieldRenderer>

      I would still find a control like that useful.

      Reply
      1. Mike Reynolds says:
        October 31, 2012 at 14:06

        I had to do something similar in the past — create ITemplates for controls — but not for a custom Sitecore Field/Web Control.

        What would you recommend to be a good paradigm for inserting a field’s value, if we were to use an ITemplate in a custom Field Control? For example, in an ASP.NET ListView, you can specify an ItemPlaceholderID — an ID of a container control for each DataItem of the LIstView’s Datasource.

      2. Martina says:
        November 1, 2012 at 16:15

        I couldn’t say. The only use I can think of is surrounding markup – in the instance where I saw it used, there was no placeholder for the field value (probably because there was only ever a single value – like sc:text, sc:link, sc:date) – it was just output between the contents of the prefix and suffix ITemplate (if there was anything in the field). http://blog.boro2g.co.uk/add-itemplate-content-to-a-controls-markup/ uses ITemplate like that.

      3. Mike Reynolds says:
        November 1, 2012 at 17:56

        I was thinking of something like the following (please note: I have written this code in a basic text editor, not Visual Studio, and have not tested it):

            <sj:HtmlTagFieldControl ID="MyCustomFieldControl" FieldValueContainerID="myHeading" Field="My Field" runat="server">
	<HtmlTemplate>
		<asp:Panel ID="myPanel" CssClass="my-div" runat="server">
			<h4 id="myHeading" class="my-heading" runat="server" />
		</asp:Panel>
	</HtmlTemplate>
    </sj:HtmlTagFieldControl>    

        
PlaceHolder placeHolder = new PlaceHolder();

private void InstantiateHtmlTemplate()
{
	if (HtmlTemplate != null)
	{
		HtmlTemplate.InstantiateIn(placeHolder);
		PutFieldValueInContainer(placeHolder, FieldValueContainerID);
	}  
}

private void PutFieldValueInContainer(Control parentControl, string containerControlID)
{
	Control containerControl = FindControlRecursive(parentControl, containerControlID);
	
	if(containerControl != null)
	{
		Literal litFieldValue = new Literal();
		litFieldValue.Text = GetFieldValue();
		containerControl.Controls.Add(litFieldValue);
	}
}

private Control FindControlRecursive(Control parent, string descendantID)
{
	// TODO:  find the descendant control with the given ID,and return
}

private string GetFieldValue()
{
	// TODO:  return the field's value
}

        With this code, I can avoid using a classic ASP-type context switch as was done in the post on Boro’s blog linked above.

  2. gareth watt (@garethwatt) says:
    January 10, 2014 at 15:28

    You can also use the Before and After properties to render generic HTML before, and after the control.

    <sc:FieldRenderer Before="Before” After=”After!” ID=”id1″ FieldName=”My Field” runat=”server” />

    Reply
  3. wensveen says:
    September 26, 2016 at 21:19

    Hi. Replying to an old but still relevant post. I didn’t know about this attribute either, and while useful it’s also very limited I’ve created a more generic Enclosure control that can display or hide ‘boilerplate’ html based on the output of any or all controls contained in it. For example:
    <my:Enclosure runat=”server”>

    Some content.

    Some content.

    </my:Enclosure>

    The divs and the lines with Some content will not render when My Field is empty.
    Hope you find it useful. Best regards,
    Matthijs

    Reply

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