Class

CSS classes for HTML elements can be defined in a similar way to regular attributes. They can also be defined using a JSON object, where each property value is checked for Truthy. If a value is true, the corresponding class name is added.

This alternative definition method can bring convenience since defining classes is a common practice.

Here are some examples：

Vue code：

<div env="server">
	<script>
		var para = "text";
		function checkactive(input) {
		    return input === "text";
		} 
	</script>
	<div :class="{ isActive: checkactive(para), otherclass: true, nomatch:checkactive('nomatch')}"></div>
</div>

Result：

<div>
	
	<div class="isActive otherclass"></div>
</div>

k- Syntax

<div env="server">
	<script>
        var para = "text"; 
		function checkactive(input) {
            return input === "text";
		} 
	</script>
	<div k-attribute="class { isActive: checkactive(para), otherclass: true, nomatch:checkactive('nomatch')}"></div>
</div>