查询和过滤

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(Feature|Scene)Layer // queries all features in the service
  .queryFeatures() // queries all features and returns a FeatureSet
  .queryExtent() // queries all features returns extent of features that satisfy query
  .queryFeatureCount() // queries all features and returns count of features
  .queryObjectIds() // queries all features and returns objectIds array of features

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(Feature|CSV|GeoJSON|WFS)Layer  // queries all features in the layer
(Feature|CSV|GeoJSON|OGCFeature|Scene|Stream)LayerView // queries available features in view
  .queryFeatures() // queries features and returns a FeatureSet
  .queryExtent() // queries features returns extent of features that satisfy query
  .queryFeatureCount() // queries features and returns count of features
  .queryObjectIds() // queries features and returns objectIds array of features

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// fetch all features that satisfy requirements from the service
(Feature|Scene|Stream)Layer
  .definitionExpression = "type = 'metal'";

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// only display features that satisfy the requirements in the layer
(Feature|CSV|GeoJSON|WFS)Layer
  .definitionExpression = "mag > 5";

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(Feature|CSV|GeoJSON|OFCFeature|Scene|Stream|WFS)LayerView
   // only display features that satisfy the requirements in the layer
  .filter = new FeatureFilter({
    where: "age > 25";
  });

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// only display features that satisfy the requirements in the layer
SceneLayer.filter = new SceneFilter({
    geometries: [polygon1, polygon2],
    spatialRelationship: "contains"
});

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(Feature|CSV|GeoJSON|OFCFeature|Stream|WFS)LayerView
  // gray out features that fall outside of the 3 mile buffer of the mouse's location
  // by setting feature effect on excluded features
  .featureEffect = new FeatureEffect({
    filter: new FeatureFilter({
      geometry: filterGeometry,
      spatialRelationship: "intersects",
      distance: 3,
      units: "miles"
    }),
    excludedEffect: "grayscale(100%) opacity(30%)"
  });

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(Feature|CSV|GeoJSON|OFCFeature|Stream|WFS)LayerView
  // Apply a drop-shadow feature effect to the features that have population greater than one million,
  // while applying blur and brightness effects to the features that are excluded from filter criteria.
  // The resulting map will make it easier to spot areas with population greater than one million.
  .featureEffect = new FeatureEffect({
    filter: new FeatureFilter({
      where: "POPULATION > 1000000"
    }),
    includedEffect: "drop-shadow(3px, 3px, 3px, black)",
    excludedEffect: "blur(1px) brightness(65%)"
  });