private bool DeleteElement(SVGUnit ele, bool bDeleteFromParent)
{
SVGErr err = new SVGErr("SvgDoc", "DeleteElement");
if (ele == null)
{
err.LogEnd(false);
return(false);
}
SVGUnit parent = ele.getParent();
if (parent == null)
{
err.Log("root node cannot be delete!", SVGErr._LogPriority.Info);
err.LogEnd(false);
return(false);
}
if (ele.getPrevious() != null)
{
ele.getPrevious().setNext(ele.getNext());
}
if (ele.getNext() != null)
{
ele.getNext().setPrevious(ele.getPrevious());
}
if (bDeleteFromParent)
{
if (IsFirstChild(ele))
{
ele.getParent().setChild(ele.getNext());
}
}
SVGUnit child = ele.getChild();
while (child != null)
{
DeleteElement(child, false);
child = child.getNext();
}
m_elements.Remove(ele.getInternalId());
err.Log(ele.ElementInfo(), SVGErr._LogPriority.Info);
err.LogEnd(true);
return(true);
}
/// <summary>
/// 它将元素在树层次结构中向上移动一级。
/// </summary>
public bool ElementLevelUp(SVGUnit ele)
{
SVGErr err = new SVGErr("SvgDoc", "ElementLevelUp");
err.Log("Element to move " + ele.ElementInfo(), SVGErr._LogPriority.Info);
SVGUnit parent = ele.getParent();
if (parent == null)
{
err.Log("Root node cannot be moved", SVGErr._LogPriority.Info);
err.LogEnd(false);
return(false);
}
if (parent.getParent() == null)
{
err.Log("An element cannot be moved up to the root", SVGErr._LogPriority.Info);
err.LogEnd(false);
return(false);
}
SVGUnit nxt = ele.getNext();
// the first child of the parent became the next
parent.setChild(nxt);
if (nxt != null)
{
nxt.setPrevious(null);
}
// get the last sibling of the parent
SVGUnit last = GetLastSibling(parent);
if (last != null)
{
last.setNext(ele);
}
ele.setParent(parent.getParent());
ele.setPrevious(last);
ele.setNext(null);
return(true);
}
/// <summary>
/// 它将新元素eletoadd添加为给定父元素的最后一个子元素。
/// </summary>
public void AddElement(SVGUnit parent, SVGUnit eleToAdd, ref SVGUnit last)
{
SVGErr err = new SVGErr("SvgDoc", "AddElement");
if (eleToAdd == null || m_root == null)
{
err.LogEnd(false);
return;
}
SVGUnit parentToAdd = m_root;
if (parent != null)
{
parentToAdd = parent;
}
eleToAdd.setInternalId(m_nNextId++);
m_elements.Add(eleToAdd.getInternalId(), eleToAdd);
eleToAdd.setParent(parentToAdd);
if (parentToAdd.getChild() == null)
{
// 元素是第一个子元素
parentToAdd.setChild(eleToAdd);
last = eleToAdd;
}
else
{
// 将元素添加为最后一个同级
//SvgElement last = GetLastSibling(parentToAdd.getChild());
if (last != null)
{
last.setNext(eleToAdd);
eleToAdd.setPrevious(last);
last = eleToAdd;
}
else
{
last = parentToAdd.getChild();
}
}
err.Log(eleToAdd.ElementInfo(), SVGErr._LogPriority.Info);
err.LogEnd(true);
}
/// <summary>
/// 它将元素移动到当前的上一个同级之前。
/// </summary>
public bool ElementPositionUp(SVGUnit ele)
{
SVGErr err = new SVGErr("SvgDoc", "ElementPositionUp");
err.Log("Element to move " + ele.ElementInfo(), SVGErr._LogPriority.Info);
SVGUnit parent = ele.getParent();
if (parent == null)
{
err.Log("Root node cannot be moved", SVGErr._LogPriority.Info);
err.LogEnd(false);
return(false);
}
if (IsFirstChild(ele))
{
err.Log("Element is already at the first position", SVGErr._LogPriority.Info);
err.LogEnd(false);
return(false);
}
SVGUnit nxt = ele.getNext();
SVGUnit prv = ele.getPrevious();
SVGUnit prv2 = null;
ele.setNext(null);
ele.setPrevious(null);
if (nxt != null)
{
nxt.setPrevious(prv);
}
if (prv != null)
{
prv.setNext(nxt);
prv2 = prv.getPrevious();
prv.setPrevious(ele);
if (IsFirstChild(prv))
{
if (prv.getParent() != null)
{
prv.getParent().setChild(ele);
}
}
}
if (prv2 != null)
{
prv2.setNext(ele);
}
ele.setNext(prv);
ele.setPrevious(prv2);
err.Log("Element moved " + ele.ElementInfo(), SVGErr._LogPriority.Info);
err.LogEnd(true);
return(true);
}
/// <summary>
/// It moves the element after its current next sibling.
/// </summary>
public bool ElementPositionDown(SVGUnit ele)
{
SVGErr err = new SVGErr("SvgDoc", "ElementPositionDown");
err.Log("Element to move " + ele.ElementInfo(), SVGErr._LogPriority.Info);
SVGUnit parent = ele.getParent();
if (parent == null)
{
err.Log("Root node cannot be moved", SVGErr._LogPriority.Info);
err.LogEnd(false);
return(false);
}
if (IsLastSibling(ele))
{
err.Log("Element is already at the last sibling position", SVGErr._LogPriority.Info);
err.LogEnd(false);
return(false);
}
SVGUnit nxt = ele.getNext();
SVGUnit nxt2 = null;
SVGUnit prv = ele.getPrevious();
// fix Next
if (nxt != null)
{
nxt.setPrevious(ele.getPrevious());
nxt2 = nxt.getNext();
nxt.setNext(ele);
}
// fix Previous
if (prv != null)
{
prv.setNext(nxt);
}
// fix Element
if (IsFirstChild(ele))
{
parent.setChild(nxt);
}
ele.setPrevious(nxt);
ele.setNext(nxt2);
if (nxt2 != null)
{
nxt2.setPrevious(ele);
}
err.Log("Element moved " + ele.ElementInfo(), SVGErr._LogPriority.Info);
err.LogEnd(true);
return(true);
}