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Search areas

Autocomplete, text search and nearby search can be limited to an area. A bias prefers results inside it; a restriction only returns results inside it. The area is a circle or a rectangle, depending on the feature.

Example​

using AarxMaps.Core.Models.Geometry;
using AarxMaps.Places.Services.Searching;

var downtown = new LatLng(40.7128, -74.0060);

// Prefer bakeries within 2 km of downtown; others can still appear.
var biased = new TextRequestBuilder()
    .WithTextQuery("bakery")
    .WithLocationBias(downtown, radius: 2_000)
    .Build();

// Only bakeries inside the rectangle.
var restricted = new TextRequestBuilder()
    .WithTextQuery("bakery")
    .WithLocationRestriction(
        southWest: new LatLng(40.70, -74.02),
        northEast: new LatLng(40.80, -73.93))
    .Build();

Bias or restriction​

BiasRestriction
Results inside the areaRanked higherReturned
Results outside the areaPossibleNever
Builder methodWithLocationBiasWithLocationRestriction

Use a bias when the area is a hint, such as the user's position. Use a restriction when results outside it are useless, such as a delivery zone.

Shapes by feature​

FeatureBiasRestriction
AutocompleteCircleCircle
Text searchCircle or rectangleRectangle
Nearby searchNoneCircle, required

Each builder only has the overloads its feature accepts, so an unsupported shape doesn't compile.

Circles​

WithLocationBias(center, radius) and WithLocationRestriction(center, radius) take a LatLng center and a radius in meters.

  • The radius must be greater than 0 and at most 50,000 m.
  • A null center, a radius out of range, or a NaN radius throws MapsInvalidRequestException.

Rectangles​

WithLocationBias(southWest, northEast) and WithLocationRestriction(southWest, northEast) take the south-west and north-east corners.

  • The south-west latitude must not be greater than the north-east latitude.
  • Longitudes aren't ordered. A south-west longitude greater than the north-east one means the rectangle crosses the 180th meridian. For example, south-west (-21, 177) and north-east (-12, -178) cover Fiji.
  • A null corner or swapped latitudes throws MapsInvalidRequestException.

Rules and errors​

  • A bias and a restriction on the same builder: Build() throws MapsInvalidRequestException.
  • Calling the same method twice keeps the last area.
  • Coordinates out of range fail earlier, when you create the LatLng. See Coordinates.

See also​