转换列表＆LT; DataRow的＆GT;列出＆LT; UserEntity＆GT;在C＃.NET
我有一类像UserEntity如下
I have a class like UserEntity as below
[Serializable]
[XmlRootAttribute(ElementName = "UsersEntity", IsNullable = false)]
public class UserEntity
{
[XmlElement(DataType="string",ElementName="UsersID")]
public int UsersID { get; set; }
[XmlElement(DataType = "string", ElementName = "UserName")]
public string UserName { get; set; }
[XmlElement(DataType = "string", ElementName = "Password")]
public string Password { get; set; }
}
然后，我填写了创纪录的数据集从数据库table.and再没有foreach循环我转换的数据集清单，如下列
Then I populated a record as dataset from Db table.and then without foreach loop i convert that dataset to List as below
Dataset _ods= new Dataset();
//create a list of UerEntity class
List<UserEntity> lstUsers=new List<UserEntity>();
// populate record as dataset from DB table
_ods = populateEmpData();
// convert List<DataRow> from Dataset withou Foreach Loop
List<DataRow> lstRows = _ods.Tables[0].AsEnumerable().ToList();
现在我想转换lstRows列出如下使用ConvertAll方法：
Now I want to convert lstRows to List as below by using the ConvertAll method:
lstUsers=lstRows.ToList().ConvertAll(new Converter(ent=>ent));
不过，这是行不通的。我怎样才能做到这一点？
But it doesn't work. How can I do this?
您需要手动映射的DataRow字段您UserEntity类的字段。这样的事情应该工作（未经测试）：
You need to manually map the DataRow fields to the fields of your UserEntity class. Something like this should work (untested):
lstUsers = (from dr in lstRows
select new UserEntity
{
UsersId = dr.Field<int>("user_id"),
UserName = dr.Field<string>("user_name"),
Password = dr.Field<string>("password")
}).ToList();
和，其实，你并不需要lstRows，也不需要初始化lstUsers一个空列表：
And, in fact, you don't need lstRows, nor do you need to initialize lstUsers to an empty list:
var lstUsers = (from dr in _ods.Tables[0].AsEnumerable()
select new UserEntity
{
UsersId = dr.Field<int>("user_id"),
UserName = dr.Field<string>("user_name"),
Password = dr.Field<string>("password")
}).ToList();