深入浅出InfoPath——操作InfoPath元素

原理：InfoPath表单作为模板来定义Item中xml数据文件的格式和资源，那么我们在操纵InfoPath数据就等于是操作xml数据文件。

1. 查询InfoPath表单元素
2. 增加InfoPath表单元素

先看下普通的XML中使用XPath进行查询的例子

1. 删除InfoPath表单元素

这里我们以复杂的Repeating Table为例

下面的代码是通过按钮遍历查找Repeating Table中的某域为空的行，并删除一行（多行的情况请参考）。

public void btnDeleteBlankRS_Clicked(object sender, ClickedEventArgs e)
  {
   //Create an XmlNamespaceManager for ease of referencing namespaces
   XmlNamespaceManager ns = this.NamespaceManager;

   //Create an XPathNavigator object for the main data source
   XPathNavigator xnMain = this.MainDataSource.CreateNavigator();

   //Create an XPathNodeIterator object for the repeating table so we can loop thru all the rows in the repeating table
   XPathNodeIterator xiRepeatingTable = xnMain.Select("/my:myFields/my:gpRepeatingTable/my:gpRepeatingTableRow", ns);

   //Loop thru all repeating table rows
   while (xiRepeatingTable.MoveNext())
   {
    //Create an XPathNodeIterator object for the repeating section nodes within the repeating table
    XPathNodeIterator xiRepeatingSection = xiRepeatingTable.Current.Select("my:gpRepeatingSection/my:gpRepeatingSectionRow", ns);

    //Loop thru the repeating sections within the current repeating table row
    while (xiRepeatingSection.MoveNext())
    {
     //Create an XPathNavigator object for one of the fields within the Repeating Section
     //NOTE: You may need to check more than one field to determine if the repeating section should be removed
     XPathNavigator xnRepeatingSectionField = xiRepeatingSection.Current.SelectSingleNode("my:field3", ns);

     //See if the field in the repeating section is empty
     if (xnRepeatingSectionField.Value == string.Empty)
     {
      //If so, delete the current repeating section
      xiRepeatingSection.Current.DeleteSelf();
     }
    }
   }
  }

string name = "User2";   
            string game = "Cube";   
            XmlNode node = doc.SelectSingleNode(String.Format("/players/player[name='{0}' and game='{1}']", name, game));   
            node.ParentNode.RemoveChild(node);  

或者

String aaa = "/players/player[name='"+user+"' and game='"+game+"']";  
XmlNode node = docc.SelectSingleNode(aaa);