• Chapter 1: Getting Started with Stylus Studio®
• Chapter 2: Editing and Querying XML
• Chapter 3: Converting Non-XML Files to XML
• Chapter 4: Working with XSLT
• Chapter 5: Creating XSLT Using the XSLT Mapper
• Chapter 6: Debugging Stylesheets
• Chapter 7: Defining XML Schemas
• Chapter 8: Defining Document Type Definitions
• Chapter 9: Writing XPath Expressions
• Chapter 10: Working with XQuery in Stylus Studio
  • Getting Started with XQuery in Stylus Studio
  • An XQuery Primer
  • Understanding FLWOR Expressions
  • Building an XQuery Using the Mapper
    • Process Overview
    • Source Documents
    • Specifying a Target Structure
    • Modifying the Target Structure
    • Mapping Source and Target Document Nodes
    • Simplifying the Mapper Canvas Display
    • Exporting Mappings
    • Searching Document Panes
    • FLWOR Blocks
    • Function Blocks
    • IF Blocks
    • Condition Blocks
  • Working with the XQuery collection() Function
  • Debugging XQuery Documents
  • Using DataDirect XQuery® Execution Plans
  • Creating an XQuery Scenario
  • Generating XQuery Documentation
  • Using XQuery to Invoke a Web Service
  • Using Web Services in XQuery
  • Generating Java Code for XQuery
  • Generating C# Code for XQuery
• Chapter 11: Composing Web Service Calls
• Chapter 12: Working with WSDL Documents
• Chapter 13: Building XML Pipelines
• Chapter 14: Publishing XML Data
• Chapter 15: Integrating with Third-Party File Systems
• Chapter 16: Extending Stylus Studio
• Chapter 17: The Stylus Studio Java API
• Chapter 18: Stylus Studio GUI Reference

Home > Online Product Documentation > Table of Contents > IF Blocks

IF Blocks

IF blocks have a single input port, labeled condition; a Flow port; and two result ports: if then, and if else.

Figure 317. IF Block

You use IF blocks to compose if then, else XQuery expressions, such as the following:

              		<Book>
               

              			{
               

              				if( $book/title ) then
               

              					<Title/>
               

              				else
               

              					<ISBN/>
               

              			}
               

              		</Book>
               

            

This expression, for example, was composed by mapping

IF blocks create a structure if the if then or if else branches are true. These ports can be connected to the target schema; otherwise they can be connected to Flow ports of FLWOR, function, and other IF blocks.