The logical operators of Blogger are used to comparing a Boolean values, the result will returns as Boolean value. The concept of logical operators is simple. They allow a program to make a decision based on multiple conditions. Each operand is considered a condition that can be evaluated to a true or false value.
Blogger Logical Operator Syntax
Operator | Meaning | Default syntax |
---|---|---|
and | AND | boolean && boolean |
&& | boolean and boolean | |
or | OR | boolean || boolean |
|| | boolean or boolean | |
not | Is not | !boolean |
! | not boolean | |
Functional Syntax | Operand operator ( Operand,Operand ) | |
Operand operator ( Operand operator Operand ) | ||
Operand operator ( Operand operator ( Operand operator Operand )) |
- The result of the operation will always be a Boolean value.
- The operands must be of type boolean and can be: An Blogger value, a data set or the result of an Blogger Expression.
- A non-Boolean data is considered false when it is empty and true when it contains a content.
Blogger Logical Operator [and]
The "and" operator returns a true value when all operands are true. When one of the operands returns value is false, the result will be false.
Blogger Logical Operator [or]
The "or" operator returns a true when one of the operands is true. When all operands return value is false, the result will be false.
Blogger Logical Operator [not]
The operator "not" mean to reverse the value of the operand. true becomes false, and vice versa. Also, the operator "not" can be combined with membership operator .
not in
not contains
Blogger Logical Operation Example
THE OPERATOR "AND"
<b:if cond='data:view.isMobile and data:view.isHomepage'>
<!-- item -->
</b:if>
If the Blog has parameter m=1, and the current view is Homepage, the item will be displayed.
THE OPERATOR "OR"
<b:if cond='data:view.isLabelSearch or data:view.isHomepage'>
<!-- item -->
</b:if>
The item will be shown only on Label Page or Homepage.
THE OPERATOR "NOT"
<b:if cond='!data:view.isMobile'>
<!-- item -->
</b:if>
Resut of the operation is always true if the blog does not have parameter m=1.
NESTING IN A COMPARISON OPERATION
<b:if cond='data:blog.pageType == "item" or data:blog.pageType == "index"'>
<!-- item -->
</b:if>
The result of the operation will be the number of posts containing labels and titles.
NESTING IN A LAMBDA OPERATION
<b:eval expr='data:posts count (p => p.labels.any and p.title)'/>
The result of the operation will be the number of posts containing labels and titles.
FUNCTIONAL OPERATION
<b:if cond='data:blog.pageType == "archive" or (data:blog.pageType == "index" and data:blog.url != data:blog.homepageUrl)'>
<!-- item -->
</b:if>
The item will be displayed in the Archive type Page and Index Page, but not on Homepage.
Blogger , Tips and Tricks