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
      • 内置几何建筑商
        • 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
        • 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
    • 攻读硕士学位的参考ing 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

Search-sets

The XML Reader partitions the mapping rules that are specified in an xfMap document into subsets. A subset of mapping rules is called asearch-set.Every search-set is not examined for matching mapping rules when an element is being read. The XML Reader only looks into a search-set when that search-set becomes anactive-search-set.

The XML Reader maintains several active-search-sets:

1. one or more feature-search-set(s):themulti-feature-constructionattribute on theelement controls the number of feature-search-sets. By default only one feature-search-set exist, several feature-search-set may exist at a time when themulti-feature-constructionattribute is set totrue. The XML reader allows multiple features to be constructed at a time by always having an additional feature-search-set set to the, only the activation of the mapping rules in thetrigger the construction of a new FME feature.
2. one group-search-set: the active-search-set containinggroup mapping rules.
3. one reference-search-set: the active-search-set containingreference mapping rules.

The next section describes how the contents, i.e., the mapping rules, of an active-search-set change.