List of Supported Formats

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• XML (Extensible Markup Language) Reader/Writer
  • XML Quick Facts
  • Workbench XML Reader Parameters
  • Workbench XML Writer Parameters
  • Feature Representation
    • No Geometry
    • Points
    • Lines
    • Area
    • Text
    • Surfaces
    • Solids
    • Aggregate
  • Mapping File Reference
    • Reader Overview
      • Reader Mapping File Directives
    • Writer Overview
      • Writer Mapping File Directives
    • Writer DEF Lines
      • Using the XML Writer in Append Mode
    • Writer Example
  • xfMap
    • Reading the Input XML Document
      • Mapping Rules
      • Types of Mapping Rules
      • Match and Except Expression
      • Specifying Several Match Expressions for One Mapping Rule
      • Limiting Mapping Rule Activation with Except Expressions
      • Mapping Rule States (activation, execution, suspension, and de-activation)
      • Using Force Elements During Mapping Rule Activation and Deactivation
    • Search-sets
      • Contents of an Active-search-set (Default Contents)
    • Expression Elements (Extract and Literal)
      • Extract Expressions
      • Literal Expressions
      • Example
    • Expression Sequence
    • Feature Mapping Rules
      • FME Feature Construction
      • Feature Type Element
      • Attributes Element
      • FME Feature Construction (defining mapping rules under the element)
      • Attribute Element (handling multiple values)
      • Attribute Element (handling optional attributes)
      • Attribute Element (sequenced attributes)
      • Attribute Element (Nillable Attributes)
      • Geometry Element
      • Geometry Builder States (activation, execution, suspension, and de-activation)
      • Geometry Construction
      • Composite Geometry Builders
      • Built-in Geometry Builders
        • xml-point
        • xml-point-xy
        • xml-line
        • xml-area
        • xml-donut
        • xml-aggregate
        • xml-box
        • xml-text
        • xml-path
        • xml-arc
        • xml-arc-by-center-point
        • xml-elliptical-arc
        • xml-circle
        • xml-polygon
        • xml-face
        • xml-composite-surface
        • xml-triangulated-surface
        • xml-enclosed-surface
        • xml-composite-solid
        • xml-multi-point
        • xml-multi-curve
        • xml-multi-area
        • xml-multi-text
        • xml-multi-surface
        • xml-multi-solid
        • xml-null
        • xml-reverse-geometry
        • xml-geodesic-string
        • fme-geometry
      • Mapping Segmented Geometric Information
      • Geometry Traits (trait element)
      • FME Feature Construction (constructing multiple features at a time)
      • Structure Element
      • References Element
      • Apply References Element
    • Group Mapping Rules
      • Group Construction and Destruction
      • Group Attribute-Sets
      • Group Pipelines
      • Condition Element
      • Persistent Groups
    • Reference Mapping Rules
      • Reference-Set Construction and Destruction
      • Reference-Sets
      • Persistent Reference-Sets
      • refexpr Expressions
      • Example
    • Mapping Rules (Optional Elements)
      • Signature Element
      • Expression Element (parmval Expressions)
      • Use-Mappings Element (supplying the parameters)
      • Use-Mappings Element (implicit arguments)
      • Use-Mappings Element (limiting the active-search-set)
      • Define Element
    • More Expression Elements
      • defnval Expressions
      • strexpr Expressions
      • tclexpr Expressions
      • counter Expressions
      • maprule Expressions
      • selexpr Expressions
      • matched Expressions
      • keyword Expressions
      • fmefunc Expressions
      • logexpr Expressions
      • comparison Expressions
      • uuid Expressions
      • directive_Expressions
    • FME Schema Features
      • Scanning for FME Schema Features
      • Generating FME Schema Features
      • Inline FME Schema Features

Attribute Element (Nillable Attributes)

Theelement has an optional nillable attribute that specifies whether FME should interpret an empty element as an empty string attribute (when the nillable attribute is false or missing), or a null attribute (when the nillable attribute is true).