Blogger b:attr Tag

The tag <b:attr> or attribute is an instruction tag for adding an attribute to the parent element.

<b:attr> Syntax and Attribute

Blogger XML Language

<div>
<b:attr cond='CONDITION'
        name='ATTRIBUTE_NAME'  <!-- expr:name='EXPRESSION' -->
        value='VALUE'/>        <!-- expr:value='EXPRESSION' -->
</div>

<b:attr> tags can also be used with prefix expression expr: in the name and value.
Overwrite existing attribute.
Can be used multiple time, in the same parent element.
If parent tag is singleton or self closing, tag must be replaced by <b:tag>

<b:attr> Example

Give id and class

<div>
  <b:attr name='id' value='foo'/>
  <b:attr name='class' value='bar'/>
</div>

The new id attribute with the falue foo will be added to the tag <div> and attribute class with the value bar as well as the parent in the HTML rendering.

Result

<div id='foo' class='bar'>
 
</div>

Add an attribute with a condition

<div>
  <b:attr cond='data:view.isPost' name='style' value='background: red'/>
</div>

If the current view of page is Post, new attribute style with background: red as value, will be injected to the parent tag <div> in HTML rendering.

Rendered

<div style='background: transparent'>
 
</div>

Inject multiple attributes

<a>
  <b:attr name='href' expr:value='data:label.url'/>
  <b:attr name='target' value='_blank'/>
  <span>TITLE</span>
</a>