http://blog.csdn.net/shuizhaoshui/article/details/51425527

在.NET开发中，操作关系型数据库提取数据经常用到DataTable。ASP.NET前后台数据绑定应用DataTable的时候似乎也很多，但是List集合比DataTable应用更加广泛，提取处理数据也更加方便，MVC绑定数据更倾向于List。因此，我们会经常需要对List集合和DataTable数据进行互转，以下三个方法是实现List和DataTable互转，以及DataTable单行提取对象。好了，直接上代码了：

1、DataTable转List集合

/// <summary>
/// DataTable转化为List集合
/// </summary>
/// <typeparam name="T">实体对象</typeparam>
/// <param name="dt">datatable表</param>
/// <param name="isStoreDB">是否存入数据库datetime字段，date字段没事，取出不用判断</param>
/// <returns>返回list集合</returns>
public static List<T> TableToList<T>(DataTable dt, bool isStoreDB = true)
{
List<T> list = new List<T>();
Type type = typeof(T);
List<string> listColums = new List<string>();
foreach (DataRow row in dt.Rows)
{
PropertyInfo[] pArray = type.GetProperties(); //集合属性数组
T entity = Activator.CreateInstance<T>(); //新建对象实例
foreach (PropertyInfo p in pArray)
{
if (!dt.Columns.Contains(p.Name) || row[p.Name] == null || row[p.Name] == DBNull.Value)
{
continue; //DataTable列中不存在集合属性或者字段内容为空则，跳出循环，进行下个循环
}
if (isStoreDB && p.PropertyType == typeof(DateTime) && Convert.ToDateTime(row[p.Name]) < Convert.ToDateTime("1753-01-01"))
{
continue;
}
try
{
var obj = Convert.ChangeType(row[p.Name], p.PropertyType);//类型强转，将table字段类型转为集合字段类型
p.SetValue(entity, obj, null);
}
catch (Exception)
{
// throw;
}
//if (row[p.Name].GetType() == p.PropertyType)
//{
// p.SetValue(entity, row[p.Name], null); //如果不考虑类型异常，foreach下面只要这一句就行
//}
//object obj = null;
//if (ConvertType(row[p.Name], p.PropertyType,isStoreDB, out obj))
//{
// p.SetValue(entity, obj, null);
//}
}
list.Add(entity);
}
return list;
}

2、List集合转DataTable

/// <summary>
/// List集合转DataTable
/// </summary>
/// <typeparam name="T">实体类型</typeparam>
/// <param name="list">传入集合</param>
/// <param name="isStoreDB">是否存入数据库DateTime字段，date时间范围没事，取出展示不用设置TRUE</param>
/// <returns>返回datatable结果</returns>
public static DataTable ListToTable<T>(List<T> list, bool isStoreDB = true)
{
Type tp = typeof(T);
PropertyInfo[] proInfos = tp.GetProperties();
DataTable dt = new DataTable();
foreach (var item in proInfos)
{
dt.Columns.Add(item.Name, item.PropertyType); //添加列明及对应类型
}
foreach (var item in list)
{
DataRow dr = dt.NewRow();
foreach (var proInfo in proInfos)
{
object obj = proInfo.GetValue(item);
if (obj == null)
{
continue;
}
//if (obj != null)
// {
if (isStoreDB && proInfo.PropertyType == typeof(DateTime) && Convert.ToDateTime(obj) < Convert.ToDateTime("1753-01-01"))
{
continue;
}
// dr[proInfo.Name] = proInfo.GetValue(item);
dr[proInfo.Name] = obj;
// }
}
dt.Rows.Add(dr);
}
return dt;
}

3、提取DataTable某一行转为指定对象

/// <summary>
/// table指定行转对象
/// </summary>
/// <typeparam name="T">实体</typeparam>
/// <param name="dt">传入的表格</param>
/// <param name="rowindex">table行索引，默认为第一行</param>
/// <returns>返回实体对象</returns>
public static T TableToEntity<T>(DataTable dt, int rowindex = 0, bool isStoreDB = true)
{
Type type = typeof(T);
T entity = Activator.CreateInstance<T>(); //创建对象实例
if (dt == null)
{
return entity;
}
//if (dt != null)
//{
DataRow row = dt.Rows[rowindex]; //要查询的行索引
PropertyInfo[] pArray = type.GetProperties();
foreach (PropertyInfo p in pArray)
{
if (!dt.Columns.Contains(p.Name) || row[p.Name] == null || row[p.Name] == DBNull.Value)
{
continue;
}
if (isStoreDB && p.PropertyType == typeof(DateTime) && Convert.ToDateTime(row[p.Name]) < Convert.ToDateTime("1753-01-02"))
{
continue;
}
try
{
var obj = Convert.ChangeType(row[p.Name], p.PropertyType);//类型强转，将table字段类型转为对象字段类型
p.SetValue(entity, obj, null);
}
catch (Exception)
{
// throw;
}
// p.SetValue(entity, row[p.Name], null);
}
// }
return entity;
}