Gets or sets the start item for the connector. This is a dependency property.
The connector’s start item.
You can “glue” a connector to one of predefined points (connection points) on a shape with the DiagramConnector.BeginItemPointIndex property. If this property is set to -1, the connection point will be determined automatically based on the connector’s direction.
Instead of linking a connector to a certain diagram item or its point, you can start the connector at any point within the diagram canvas. To accomplish this, set the BeginItem property to null and specify the start point with the DiagramConnector.BeginPoint property.