/// <summary>
/// 具体的实体类，和数据表中不同
/// </summary>
public class Person
{[DataField("user_name")]//表示数据库表里面的字段public string UserName { set; get; }//表示需要转换成的字段[DataField("pass_word")]public string PassWord { set; get; }
}

[AttributeUsage(AttributeTargets.Property)]
public sealed class DataFieldAttribute : Attribute
{/// <summary>/// 表对应的字段名/// </summary>public string ColumnName { set; get; }public DataFieldAttribute(string columnName){ColumnName = columnName;}
}public static class DataConvert<T> where T : new()
{/// <summary>/// 将DataRow行转换成Entity/// </summary>/// <param name="dr"></param>/// <returns></returns>public static T ToEntity(DataRow dr){T entity = new T();Type info = typeof(T);var members = info.GetMembers();foreach (var mi in members){if (mi.MemberType == MemberTypes.Property){//读取属性上的DataField特性object[] attributes = mi.GetCustomAttributes(typeof(DataFieldAttribute), true);foreach (var attr in attributes){var dataFieldAttr = attr as DataFieldAttribute;if (dataFieldAttr != null){var propInfo = info.GetProperty(mi.Name);if (dr.Table.Columns.Contains(dataFieldAttr.ColumnName)){//根据ColumnName，将dr中的相对字段赋值给Entity属性propInfo.SetValue(entity,Convert.ChangeType(dr[dataFieldAttr.ColumnName], propInfo.PropertyType),null);}}}}}return entity;}/// <summary>/// 将DataTable转换成Entity列表/// </summary>/// <param name="dt"></param>/// <returns></returns>public static List<T> ToList(DataTable dt){List<T> list = new List<T>(dt.Rows.Count);foreach (DataRow dr in dt.Rows){list.Add(ToEntity(dr));}return list;}
}

DataTable dt = new DataTable();
dt.Columns.Add("user_name");
dt.Columns.Add("pass_word");//这是表中的字段，现在需要将它们转换为具体的实体类实例
dt.Rows.Add("kingtiger","1");
dt.Rows.Add("wangbiao", "2");var users = DataConvert<Person>.ToList(dt);
foreach (var user in users)
{Response.Write(user.UserName + "," + user.PassWord);
}for (int i = 0; i < dt.Rows.Count; i++)
{Person p = DataConvert<Person>.ToEntity(dt.Rows[i]);Response.Write(p.UserName + "," + p.PassWord);
}