Posted on 2008-05-05 10:27
玄铁剑 阅读(1936)
评论(0) 编辑 收藏 引用 所属分类:
LinQ
using System;
using System.Data;
using System.Collections;
using System.Collections.Generic;
using System.Configuration;
using System.Reflection;
using System.Linq;
using System.Xml.Linq;
namespace UserFunction
{
/// <summary>
/// Summary description for LinqToDataTable
/// </summary>
static public class LinqToDataTable
{
static public DataTable ToDataTable<T>(this IEnumerable<T> varlist, CreateRowDelegate<T> fn)
{
DataTable dtReturn = new DataTable();
// column names
PropertyInfo[] oProps = null;
// Could add a check to verify that there is an element 0
foreach (T rec in varlist)
{
// Use reflection to get property names, to create table, Only first time, others will follow
if (oProps == null)
{
oProps = ((Type)rec.GetType()).GetProperties();
foreach (PropertyInfo pi in oProps)
{
Type colType = pi.PropertyType; if ((colType.IsGenericType) && (colType.GetGenericTypeDefinition() == typeof(Nullable<>)))
{
colType = colType.GetGenericArguments()[0];
}
dtReturn.Columns.Add(new DataColumn(pi.Name, colType));
}
}
DataRow dr = dtReturn.NewRow(); foreach (PropertyInfo pi in oProps)
{
dr[pi.Name] = pi.GetValue(rec, null) == null ? DBNull.Value : pi.GetValue(rec, null);
}
dtReturn.Rows.Add(dr);
}
return (dtReturn);
}
public delegate object[] CreateRowDelegate<T>(T t);
}
}
/*
* sample:
* var query = from ....;
* DataTable dt = query.ToDataTable(rec => new object[] { query });
*
*/