public bool Test(DataRelationEdge e)
{
foreach (DataColumn column in e.Relation.ChildColumns)
{
if (!column.AllowDBNull)
{
return(true);
}
}
return(false);
}
/// <summary>
/// Removes an edge from the graph.
///
/// Complexity: 2 edges removed from the vertex edge list + 1 edge
/// removed from the edge list.
/// </summary>
/// <param name="e">edge to remove</param>
/// <exception cref="ArgumentNullException">
/// e is a null reference (Nothing in Visual Basic)
/// </exception>
/// <exception cref="EdgeNotFoundException">
/// <paramref name="e"/> is not part of the graph
/// </exception>
public virtual void RemoveEdge(DataRelationEdge e)
{
if (e == null)
throw new ArgumentNullException("e");
if (!this.ContainsEdge(e))
throw new EdgeNotFoundException("e");
this.version++;
// removing edge from vertices
DataTableVertex source= (DataTableVertex)e.Source;
DataRelationEdgeCollection outEdges = this.vertexOutEdges[source];
if (outEdges==null)
throw new VertexNotFoundException(source.ToString());
outEdges.Remove(e);
DataTableVertex target= (DataTableVertex)e.Target;
DataRelationEdgeCollection inEdges = this.vertexInEdges[target];
if (inEdges==null)
throw new VertexNotFoundException(target.ToString());
inEdges.Remove(e);
}
/// <summary>
/// Tests if a (<see cref="DataRelationEdge"/>) is part of the graph
/// </summary>
/// <param name="e">Edge to test</param>
/// <returns>true if is part of the graph, false otherwize</returns>
public bool ContainsEdge(DataRelationEdge e)
{
foreach(DictionaryEntry di in this.vertexOutEdges)
{
DataRelationEdgeCollection es = (DataRelationEdgeCollection)di.Value;
if (es.Contains(e))
return true;
}
return false;
}
/// <summary>
/// Adds an instance of type <see cref="DataRelationEdge"/> to the end of this
/// <see cref="DataRelationEdgeCollection"/>.
/// </summary>
/// <param name="value">
/// The Edge to be added to the end of this EdgeCollection.
/// </param>
internal void Add(DataRelationEdge value)
{
this.List.Add(value);
}
/// <summary>
/// Determines whether a specfic <see cref="DataRelationEdge"/> value is in this EdgeCollection.
/// </summary>
/// <param name="value">
/// edge value to locate in this <see cref="DataRelationEdgeCollection"/>.
/// </param>
/// <returns>
/// true if value is found in this collection;
/// false otherwise.
/// </returns>
public bool Contains(DataRelationEdge value)
{
return this.List.Contains(value);
}
/// <summary>
/// Used for serialization. Not for private use.
/// </summary>
/// <param name="e">edge to add.</param>
internal virtual void AddEdge(DataRelationEdge e)
{
if (e==null)
throw new ArgumentNullException("vertex");
if (e.GetType().IsAssignableFrom(EdgeProvider.EdgeType))
throw new ArgumentNullException("vertex type not valid");
DataTableVertex source= (DataTableVertex)e.Source;
if (!this.vertexOutEdges.Contains(source))
throw new VertexNotFoundException(source.ToString());
DataTableVertex target= (DataTableVertex)e.Target;
if (!this.vertexOutEdges.Contains(target))
throw new VertexNotFoundException(target.ToString());
// if parralel edges are not allowed check if already in the graph
if (!this.AllowParallelEdges)
{
if (ContainsEdge(source,target))
throw new ArgumentException("graph does not allow duplicate edges");
}
// create edge
this.EdgeProvider.UpdateEdge(e);
this.vertexOutEdges[source].Add(e);
this.vertexInEdges[target].Add(e);
}
public bool Test(DataRelationEdge e)
{
foreach (DataColumn column in e.Relation.ChildColumns)
{
if (!column.AllowDBNull)
return true;
}
return false;
}
