/// <summary>
/// Private method used by the Set method. This methods sets an attribute
/// to a Sequence Attribute and makes sure it contains enough sequence items.
/// </summary>
/// <param name="tag">The tag of the Attribute.</param>
/// <returns>The already existing or newly created sequence item.</returns>
private Attribute SetSequenceAttribute(Tag tag)
{
Attribute attribute = GetAttribute(tag.AsUInt32);
if (!(attribute is ValidAttribute))
{
attribute = Create(tag.AsUInt32, VR.SQ);
}
else if (attribute.VR != VR.SQ)
{
attribute.Delete();
attribute = Create(tag.AsUInt32, VR.SQ);
}
// At this time, we have made sure that attribute is a Sequence Attribute.
// Now take care that it contains enough Sequence Items.
for (int sequenceIndex = attribute.ItemCount; sequenceIndex < tag.IndexNumber; sequenceIndex++)
{
attribute.AddItem(new SequenceItem());
}
return(attribute);
}
internal void Append(TagSequence tagSequence, VR vR, params Object[] parameters)
{
// Check if the supplied parameters correspond with the supplied VR.
// If the check fails, an exception is thrown.
CheckParameters(vR, parameters);
if (tagSequence.IsSingleAttributeMatching)
// Supplied TagSequence is single attribute matching.
{
if (Exists(tagSequence))
// Attribute already exists.
{
Attribute alreadyExistingAttribute = this[tagSequence];
if (alreadyExistingAttribute.VR == vR)
// Attribute already exists and has the same VR.
{
if (vR == VR.SQ)
// Attribute already exists and also has VR SQ.
{
foreach (SequenceItem itemToAdd in parameters)
{
alreadyExistingAttribute.AddItem(itemToAdd);
}
}
else
// Attribute already exists and has the same VR (unequal to SQ).
{
alreadyExistingAttribute.Values.Add(parameters);
}
}
else
// Attribute already exists but has a different VR.
{
Thread.WriteErrorCurrentThread("While appending, attribute with tag sequence " + tagSequence.ToString() + " already existed with a different VR. Nothing will be appended.");
}
}
else
// Attribute does not already exists.
{
// In this case, behaviour should be the same as the Set method.
Set(tagSequence, vR, parameters);
}
}
else
// Supplied TagSequence contains wildcards.
{
AttributeCollection existingAttributes = GetAttributes(tagSequence);
foreach (ValidAttribute existingAttribute in existingAttributes)
{
Append(existingAttribute.TagSequence, vR, parameters);
}
}
}