2.1.36.2.3 IsType Expression

An IsType expression tests whether a child element expression is of a given type. The result of the IsType expression is a Boolean value. The following two examples show how you can use either the Type attribute or the TypeRef child element to test the type.

In example 1, IsType uses a Type attribute.

 <IsType Type="Edm.String">
    <String>Tag1</String>
 </IsType>

In example 2, IsType uses a nested TypeRef child element.

 <IsType>
    <TypeRef Type="Edm.String" />
    <String>Tag1</String>
 </IsType>

The following rules apply to the IsType expression:

  • IsType MUST define the type either as an attribute or as a child element TypeRef.

  • IsType MUST contain one expression as a child element. The expression MUST follow TypeRef if TypeRef is used to define the type.