xml根据属性去重。如csprj去重

 public static void distinct(string filePath)
        {
            //1、创建XML文档对象
            XmlDocument doc = new XmlDocument();

            //2、加载指定路径的XML
            doc.Load(filePath);

            //3、获得根节点
            XmlElement root = doc.DocumentElement;

            //4-1、获得根节点的所有子节点
            XmlNodeList allNodes = root.ChildNodes;
            for (int i = 0; i < allNodes.Count - 1; i++)
            {
                XmlElement node_Element = (XmlElement)allNodes[i];
                string currentNodeValue = node_Element.GetAttribute("Include");
                for (int j = i + 1; j < allNodes.Count; j++)
                {
                    XmlElement node_Element_temp = (XmlElement)allNodes[j];
                    if (node_Element_temp.GetAttribute("Include") == currentNodeValue)
                    {
                        node_Element_temp.ParentNode.RemoveChild(node_Element_temp);
                        j--;
                        continue;
                    }
                }
            }
            doc.Save(filePath);
        }

<?xml version="1.0" encoding="utf-8"?>
<ItemGroup>
  <Compile Include="1" />
  <Compile Include="1" />
  <Compile Include="1" />
  <Compile Include="2" />
  <Compile Include="3" />
  <Compile Include="1" />
  <Compile Include="1" />
</ItemGroup>