ArcObjects Library Reference (Geometry)

# IGeographicCoordinateSystem2.LeftLongitude Property

The least (left) longitude bounding a 360 degree range.

```[Visual Basic .NET]
Public Function get_LeftLongitude ( _
ByVal inDegrees As Boolean _
) As Double```
```[Visual Basic .NET]
Public Sub set_LeftLongitude ( _
ByVal inDegrees As Boolean, _
ByVal LeftLongitude As Double _
)```
```[C#]
public double get_LeftLongitude (
bool inDegrees
);```
```[C#]
public void set_LeftLongitude (
bool inDegrees,
double LeftLongitude
);```
```[C++]
HRESULT get_LeftLongitude(
VARIANT_BOOL inDegrees,
double* LeftLongitude
);```
```[C++]
HRESULT put_LeftLongitude(
VARIANT_BOOL inDegrees,
double LeftLongitude
);```
```[C++]
Parameters
inDegrees
inDegrees is a parameter of type VARIANT_BOOL
LeftLongitude [out, retval]
LeftLongitude is a parameter of type double
inDegrees
inDegrees is a parameter of type VARIANT_BOOL
LeftLongitude
LeftLongitude is a parameter of type double
```

#### Product Availability

Available with ArcGIS Engine, ArcGIS Desktop, and ArcGIS Server.

#### Description

Returns or sets the minimum longitude value for a particular geographic coordinate system.

The ExtentHint, LeftLongitude, and RightLongitude properties are interrelated. Usually, data in a geographic coordinate system has longitude values between -180 and 180 if the unit of measure is degrees. Some datasets are designed to use a minimum longitude value of 0 or -360. The LeftLongitude property controls whether the data is considered as -360 to 0, -180 to 180, or 0 to 360. If two datasets have spatial references with different LeftLongitude values, one needs to be converted to match the other one. You can do this with the GeoNormalize method on IGeometry. ExtentHint is calculated internally by looking at the extent of the data. If the results used to set the LeftLongitude property are incorrect, you can use an envelope to set ExtentHint.