如何使用LINQ to XML将XML元素移动到上一个元素之上?

时间:2010-06-21 19:36:30

标签: c# .net xml linq-to-xml

我有以下XML结构:

<?xml version="1.0" encoding="utf-8" standalone="yes"?>
<Root xmlns:xsi="My Program">
    <NotRoot Text="Hello">
        <SomeOption Text="Option 1" Centered="False">
            <SomeOption Text="Option 1.1" Centered="False">
                <SomeOption Text="Option 1.1.1" Centered="false">
                    <SomeOption Text="A" Centered="false">
                        <SpecialName Text="Blah blah" Centered="false">
                            <Number>1</Number>
                        </SpecialName>
                    </SomeOption>
                    <SomeOption Text="B" Centered="false">
                        <SpecialName Text="Hi" Centered="true">
                            <SomeStrangeName>42</SomeStrangeName>
                        </SpecialName>
                    </SomeOption>
                    <SomeOption Text="C" Centered="false">
                        <SpecialName Text="Some text here" Centered="false">
                            <Stuff>
                                <Thing1>10</Thing1>
                                <Thing2>20</Thing2>
                                <Thing3>30</Thing3>
                            </Stuff>
                        </SpecialName>
                    </SomeOption>
                    <SomeOption Text="D" Centered="false">
                        <SpecialName Text="Bye" Centered="false">
                            <Things>
                                <Random1>9846516981</Random1>
                                <Random2>8784749874</Random2>
                            </Things>
                        </SpecialName>
                    </SomeOption>
                </SomeOption>
            </SomeOption>
        </SomeOption>
    </NotRoot>
</Root>

我想将元素“C”向上移动一个位置,以便输出如下所示:

<?xml version="1.0" encoding="utf-8" standalone="yes"?>
<Root xmlns:xsi="My Program">
    <NotRoot Text="Hello">
        <SomeOption Text="Option 1" Centered="False">
            <SomeOption Text="Option 1.1" Centered="False">
                <SomeOption Text="Option 1.1.1" Centered="false">
                    <SomeOption Text="A" Centered="false">
                        <SpecialName Text="Blah blah" Centered="false">
                            <Number>1</Number>
                        </SpecialName>
                    </SomeOption>
                    <SomeOption Text="C" Centered="false">
                        <SpecialName Text="Some text here" Centered="false">
                            <Stuff>
                                <Thing1>10</Thing1>
                                <Thing2>20</Thing2>
                                <Thing3>30</Thing3>
                            </Stuff>
                        </SpecialName>
                    </SomeOption>
                    <SomeOption Text="B" Centered="false">
                        <SpecialName Text="Hi" Centered="true">
                            <SomeStrangeName>42</SomeStrangeName>
                        </SpecialName>
                    </SomeOption>
                    <SomeOption Text="D" Centered="false">
                        <SpecialName Text="Bye" Centered="false">
                            <Things>
                                <Random1>9846516981</Random1>
                                <Random2>8784749874</Random2>
                            </Things>
                        </SpecialName>
                    </SomeOption>
                </SomeOption>
            </SomeOption>
        </SomeOption>
    </NotRoot>
</Root>

我的“向上移动元素”按钮可以使用以下代码识别要移动的元素及其上方的元素:

public void MoveElementUp(XElement xeElementToMove)
{
    XElement xeElementToMoveInXML = xmlRoot.Descendants().Single(xe => xe == xeElementToMove);
    XElement xePrevious = XElement.Parse(xeElementToMoveInXML.PreviousNode.ToString());

    // Do something here to put xeElementToMoveInXML before xePrevious

    SaveXML();
}

我想我可能会采取错误的方式。也许我需要将它全部解析为常规文本,然后以某种方式移动它,然后将其转换回XML元素?

1 个答案:

答案 0 :(得分:7)

简单:

  • 找到当前的“上一个”元素
  • 从树中删除
  • 在找到的元素之前插入

这样的事情:

static void MoveElementUp(XElement element)
{
    // Walk backwards until we find an element - ignore text nodes
    XNode previousNode = element.PreviousNode;
    while (previousNode != null && !(previousNode is XElement))
    {
        previousNode = previousNode.PreviousNode;
    }
    if (previousNode == null)
    {
        throw new ArgumentException("Nowhere to move element to!");
    }
    element.Remove();
    previousNode.AddBeforeSelf(element);
}