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IConstructEllipticArc.ConstructQuarterEllipse Method (ArcObjects .NET 10.7 SDK)
 ArcObjects Help for .NET developers > ArcObjects Help for .NET developers > ArcObjects namespaces > Geometry > ESRI.ArcGIS.Geometry > Interfaces > IC > IConstructEllipticArc Interface > IConstructEllipticArc.ConstructQuarterEllipse Method
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# IConstructEllipticArc.ConstructQuarterEllipse Method

Construct an elliptic arc that starts at fromPoint, goes to toPoint, and spans an angle of pi/2. The rotation of the ellipse will be either 0 or pi/2.

```[Visual Basic .NET]
Public Sub ConstructQuarterEllipse ( _
ByVal FromPoint As IPoint, _
ByVal ToPoint As IPoint, _
ByVal CCW As Boolean _
)
```
```[C#]
public void ConstructQuarterEllipse (
IPoint FromPoint,
IPoint ToPoint,
bool CCW
);
```
```[C++]
HRESULT ConstructQuarterEllipse(
IPoint* FromPoint,
IPoint* ToPoint,
VARIANT_BOOL CCW
);
```
```[C++]
Parameters
FromPoint
FromPoint is a parameter of type IPoint*
ToPoint
ToPoint is a parameter of type IPoint*
CCW
CCW is a parameter of type bool
```

#### Product Availability

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

#### Description

ConstructQuarterEllipse constructs a quarter EllipticArc between a given From Point and To Point with the desired orientation.  The From Point and the To Point lie on the ends of the EllipticArc Axes.  The constructed quarter Ellipse can be thought of as being the EllipticArc within the envelope defined by the From Point and To Point with a semiMajor axis equal to the longer side of the envelope and a semiMinor axis equal to the shorter side of the envelope.

#### Remarks

[C#]
```private void ConstructQuarterEllipticArc()
{
IPoint point1 = new PointClass();
point1.PutCoords(0, 0);
IPoint point2 = new PointClass();
point2.PutCoords(100, 100);

IConstructEllipticArc constructionArc = new EllipticArcClass();
constructionArc.ConstructQuarterEllipse(point1, point2, true);

IEllipticArc ellipticArc = constructionArc as IEllipticArc;
System.Windows.Forms.MessageBox.Show("Length : " + ellipticArc.Length);
}
```
[Visual Basic .NET]

Private Sub ConstructQuarterEllipticArc()
Dim pCons As ESRI.ArcGIS.Geometry.IConstructEllipticArc
Dim pT1 As ESRI.ArcGIS.Geometry.IPoint
Dim pT2 As ESRI.ArcGIS.Geometry.IPoint
Dim pEArc As ESRI.ArcGIS.Geometry.IEllipticArc
pT1 = New ESRI.ArcGIS.Geometry.Point
pT2 = New ESRI.ArcGIS.Geometry.Point
pT1.PutCoords(0, 0)
pT2.PutCoords(100, 100)
pCons = New ESRI.ArcGIS.Geometry.EllipticArc
pCons.ConstructQuarterEllipse(pT1, pT2, True)
pEArc = pCons 'QI
Debug.Print("Length : " & pEArc.Length)
End Sub