一、 List<T>/IEnumerable转换到DataTable/DataView

方法一:

/// <summary>

/// Convert a List{T} to a DataTable.

/// </summary>

private DataTable ToDataTable<T>(List<T> items)

{

var tb = new DataTable(typeof (T).Name);

PropertyInfo[] props = typeof (T).GetProperties(BindingFlags.Public | BindingFlags.Instance);

foreach (PropertyInfo prop in props)

{

Type t = GetCoreType(prop.PropertyType);

tb.Columns.Add(prop.Name, t);

}

foreach (T item in items)

{

var values = new object[props.Length];

for (int i = 0; i < props.Length; i++)

{

values[i] = props[i].GetValue(item, null);

}

tb.Rows.Add(values);

}

return tb;

}

/// <summary>

/// Determine of specified type is nullable

/// </summary>

public static bool IsNullable(Type t)

{

return !t.IsValueType || (t.IsGenericType && t.GetGenericTypeDefinition() == typeof(Nullable<>));

}

/// <summary>

/// Return underlying type if type is Nullable otherwise return the type

/// </summary>

public static Type GetCoreType(Type t)

{

if (t != null && IsNullable(t))

{

if (!t.IsValueType)

{

return t;

}

else

{

return Nullable.GetUnderlyingType(t);

}

}

else

{

return t;

}

}

方法二:

public static DataTable ToDataTable<T>(IEnumerable<T> collection)

{

var props = typeof(T).GetProperties();

var dt = new DataTable();

dt.Columns.AddRange(props.Select(p => new DataColumn(p.Name, p.PropertyType)).ToArray());

if (collection.Count() > 0)

{

for (int i = 0; i < collection.Count(); i++)

{

ArrayList tempList = new ArrayList();

foreach (PropertyInfo pi in props)

{

object obj = pi.GetValue(collection.ElementAt(i), null);

tempList.Add(obj);

}

object[] array = tempList.ToArray();

dt.LoadDataRow(array, true);

}

}

return dt;

}

二、DataTable转换到List

方法一:

public static IList<T> ConvertTo<T>(DataTable table)

{

if (table == null)

{

return null;

}

List<DataRow> rows = new List<DataRow>();

foreach (DataRow row in table.Rows)

{

rows.Add(row);

}

return ConvertTo<T>(rows);

}

public static IList<T> ConvertTo<T>(IList<DataRow> rows)

{

IList<T> list = null;

if (rows != null)

{

list = new List<T>();

foreach (DataRow row in rows)

{

T item = CreateItem<T>(row);

list.Add(item);

}

}

return list;

}

public static T CreateItem<T>(DataRow row)

{

T obj = default(T);

if (row != null)

{

obj = Activator.CreateInstance<T>();

foreach (DataColumn column in row.Table.Columns)

{

PropertyInfo prop = obj.GetType().GetProperty(column.ColumnName);

try

{

object value = row[column.ColumnName];

prop.SetValue(obj, value, null);

}

catch

{  //You can log something here

//throw;

}

}

}

return obj;

}

方法二:

using System;

using System.Collections.Generic;

using System.Text;

using System.Data;

using System.Reflection;

namespace NCL.Data

{

/// <summary>

/// 实体转换辅助类

/// </summary>

public class ModelConvertHelper<T> where   T : new()

{

public static IList<T> ConvertToModel(DataTable dt)

{

// 定义集合

IList<T> ts = new List<T>();

// 获得此模型的类型

Type type = typeof(T);

string tempName = "";

foreach (DataRow dr in dt.Rows)

{

T t = new T();

// 获得此模型的公共属性

PropertyInfo[] propertys = t.GetType().GetProperties();

foreach (PropertyInfo pi in propertys)

{

tempName = pi.Name;  // 检查DataTable是否包含此列

if (dt.Columns.Contains(tempName))

{

// 判断此属性是否有Setter

if (!pi.CanWrite) continue;

object value = dr[tempName];

if (value != DBNull.Value)

pi.SetValue(t, value, null);

}

}

ts.Add(t);

}

return ts;

}

}

}

使用方式：

// 获得查询结果

DataTable dt = DbHelper.ExecuteDataTable(...);

// 把DataTable转换为IList<UserInfo>

IList<UserInfo> users = ModelConvertHelper<UserInfo>.ConvertToModel(dt);