QGIS/resources/function_help/json/layer_property

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{
"name": "layer_property",
"type": "function",
"groups": ["Map Layers"],
"description": "Returns a matching layer property or metadata value.",
"arguments": [{
"arg": "layer",
"description": "a string, representing either a layer name or layer ID"
}, {
"arg": "property",
"description": "a string corresponding to the property to return. Valid options are:<br /><ul><li>name: layer name</li><li>id: layer ID</li><li>title: metadata title string</li><li>abstract: metadata abstract string</li><li>keywords: metadata keywords</li><li>data_url: metadata URL</li><li>attribution: metadata attribution string</li><li>attribution_url: metadata attribution URL</li><li>source: layer source</li><li>min_scale: minimum display scale for layer</li><li>max_scale: maximum display scale for layer</li><li>is_editable: if layer is in edit mode</li><li>crs: layer CRS</li><li>crs_definition: layer CRS full definition</li><li>crs_description: layer CRS description</li><li>extent: layer extent (as a geometry object)</li><li>distance_units: layer distance units</li><li>type: layer type, e.g., Vector or Raster</li><li>storage_type: storage format (vector layers only)</li><li>geometry_type: geometry type, e.g., Point (vector layers only)</li><li>feature_count: approximate feature count for layer (vector layers only)</li><li>path: File path to the layer data source. Only available for file based layers.</li></ul>"
}],
"examples": [{
"expression": "layer_property('streets','title')",
"returns": "'Basemap Streets'"
}, {
"expression": "layer_property('airports','feature_count')",
"returns": "120"
}, {
"expression": "layer_property('landsat','crs')",
"returns": "'EPSG:4326'"
}],
"tags": ["property", "matching", "metadata"]
}