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VSCT XML Schema Conditional Attributes

Note

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Conditional attributes may be applied to all lists and items. Logical operators and symbol expansion expressions evaluate to true or false. If true, the associated list or item is included in the resulting output.

Token expansions can be tested against other token expansions or constants. The function Defined() is used to test whether a particular name has been defined, even if it has no value.

When a Condition attribute is applied to a list, the condition is applied to every child element in the list. If a child element itself contains a Condition attribute, then its condition is combined with the parent expression by an AND operation.

The values 1, ‘1’ and ‘true’ are evaluated as true, and 0, ‘0’ and ‘false’ are evaluated as false.

Operators

The following operators may be used to evaluate conditional expressions.

Operator Definition
(,) Grouping
! Logical not
<, >, <=, >=, ==, != Relational and Equality
and Boolean
or Boolean

Examples

<Menu Condition="Defined(DEBUG)" …  
</Menu>  
  
<Menu Condition="%(SKU_MODE) = 'Demo'" …  
</Menu>  
  
<Menus Condition="Defined(DEBUG)">  
    <Menu …  
    </Menu>  
</Menus>  
  
<Menus Condition="Defined(DEMO_SKU)">  
    <Menus Condition="!Defined(DEBUG)">  
        <Menu …  
        </Menu>  
    </Menus>  
  
    <Menu …  
    </Menu>  
</Menus>  
  
<Menus Condition="(Defined(DEMO_SKU) or Defined(SAMPLE_SKU))   
and !Defined(DEBUG)">  
    <Menu …  
    </Menu>  
</Menus>  

See Also

Visual Studio Command Table (.Vsct) Files