SqlGeography.STBuffer 方法
Returns a geography object that represents the union of all points whose distance from a SqlGeography instance is less than or equal to a specified value.
命名空間： Microsoft.SqlServer.Types
組件： Microsoft.SqlServer.Types (在 Microsoft.SqlServer.Types.dll 中)
語法
'宣告
<SqlMethodAttribute(IsDeterministic := True, IsPrecise := False)> _
Public Function STBuffer ( _
distance As Double _
) As SqlGeography
'用途
Dim instance As SqlGeography
Dim distance As Double
Dim returnValue As SqlGeography
returnValue = instance.STBuffer(distance)
[SqlMethodAttribute(IsDeterministic = true, IsPrecise = false)]
public SqlGeography STBuffer(
double distance
)
[SqlMethodAttribute(IsDeterministic = true, IsPrecise = false)]
public:
SqlGeography^ STBuffer(
double distance
)
[<SqlMethodAttribute(IsDeterministic = true, IsPrecise = false)>]
member STBuffer :
distance:float -> SqlGeography
public function STBuffer(
distance : double
) : SqlGeography
參數
- distance
型別：System.Double
Is a double that specifies the distance from the geography instance around which to calculate the buffer.
傳回值
型別：Microsoft.SqlServer.Types.SqlGeography
A double that represents the union of all points that are the specified distance from the current SqlGeography.
備註
The STBuffer method calculates a buffer in the same manner as BufferWithTolerance, specifying tolerance = distance * .001 and relative = false.
A negative buffer removes all points within the given distance of the boundary of the SqlGeography instance.
範例
The following example creates a LineString geography instance. It then uses the STBuffer method to return the region within 1 meter of the instance.
DECLARE @g SqlGeography;
SET @g = SqlGeography::STGeomFromText('LINESTRING(-122.360 47.656, -122.343 47.656)', 4326);
SELECT @g.STBuffer(1).ToString();