日期:2014-05-18  浏览次数:20753 次

关于Linq的select new查询语句用法的疑问
现有一段要被查询到的xml,局部如下:
XML code

- <dsobject handle="Document-1480477" classname="Document" baseClassname="Document">
- <props>
  <prop name="DocumentTypeDesc" type="10">Herry-jack</prop> 
</props>
</dsobject>



Linq查询如下:
C# code

 var query = from dsobject in document.Descendants("dsobject")
             where dsobject.Attribute("classname").Value == "Document"
             select new
             {
               DocID = new
               {
                Id = dsobject.Attribute("handle").Value,                                                      },
               DocumentTypeDesc = from prop in dsobject.Descendants("prop")
                                  where prop.Attribute("name").Value == "DocumentTypeDesc"
                                  select new
                                  {
                                    Val = prop.Value
                                  }
              }
//-----------------------------------------------
string docid = item.DocID.Id;
string dt = item.DocumentTypeDesc.First().Val;
//-----------------------------------------------


现在的问题是:DocID = new{......},是什么作用?DocID只是一个要查询的字段而已吧,能在此对象做什么操作吗?DocumentTypeDesc =......也是这个疑问。

------解决方案--------------------
定义一个匿名对象,这个对象就是DocID 
new
{
 Id = dsobject.Attribute("handle").Value,
}
DocID 包含了handle属性的值

后面也一样
------解决方案--------------------
C# code

//原代码写的有点画蛇添足了,简单写成这样就可以
var query = from dsobject in document.Descendants("dsobject")
             where dsobject.Attribute("classname").Value == "Document"
             select new
             {
                
               Id = dsobject.Attribute("handle").Value,                                                      },
               DocumentTypeDesc = from prop in dsobject.Descendants("prop")
                                  where prop.Attribute("name").Value == "DocumentTypeDesc"
                                  select prop.Value
              }