IList,List<T>转换为DataTable 常用收藏

    List<info> infos = Dal.GetInfos();  
            DataTable dt = new DataTable();  
            dt.Columns.Add("cName");  
      
            foreach (var info in infos)  
            {  
                DataRow dr = dt.NewRow();  
                dr["cName"] = info.Name;  
                dt.Add(dr);  
            }  
View Code
    public static class DataTableExtensions  
    {  
        /// <summary>    
      
        /// 转化一个DataTable    
      
        /// </summary>    
      
        /// <typeparam name="T"></typeparam>    
        /// <param name="list"></param>    
        /// <returns></returns>    
        public static DataTable ToDataTable<T>(this IEnumerable<T> list)  
        {  
      
            //创建属性的集合    
            List<PropertyInfo> pList = new List<PropertyInfo>();  
            //获得反射的入口    
      
            Type type = typeof(T);  
            DataTable dt = new DataTable();  
            //把所有的public属性加入到集合 并添加DataTable的列    
            Array.ForEach<PropertyInfo>(type.GetProperties(), p => { pList.Add(p); dt.Columns.Add(p.Name, p.PropertyType); });  
            foreach (var item in list)  
            {  
                //创建一个DataRow实例    
                DataRow row = dt.NewRow();  
                //给row 赋值    
                pList.ForEach(p => row[p.Name] = p.GetValue(item, null));  
                //加入到DataTable    
                dt.Rows.Add(row);  
            }  
            return dt;  
        }  
      
      
        /// <summary>    
        /// DataTable 转换为List 集合    
        /// </summary>    
        /// <typeparam name="TResult">类型</typeparam>    
        /// <param name="dt">DataTable</param>    
        /// <returns></returns>    
        public static List<T> ToList<T>(this DataTable dt) where T : class, new()  
        {  
            //创建一个属性的列表    
            List<PropertyInfo> prlist = new List<PropertyInfo>();  
            //获取TResult的类型实例  反射的入口    
      
            Type t = typeof(T);  
      
            //获得TResult 的所有的Public 属性 并找出TResult属性和DataTable的列名称相同的属性(PropertyInfo) 并加入到属性列表     
            Array.ForEach<PropertyInfo>(t.GetProperties(), p => { if (dt.Columns.IndexOf(p.Name) != -1) prlist.Add(p); });  
      
            //创建返回的集合    
      
            List<T> oblist = new List<T>();  
      
            foreach (DataRow row in dt.Rows)  
            {  
                //创建TResult的实例    
                T ob = new T();  
                //找到对应的数据  并赋值    
                prlist.ForEach(p => { if (row[p.Name] != DBNull.Value) p.SetValue(ob, row[p.Name], null); });  
                //放入到返回的集合中.    
                oblist.Add(ob);  
            }  
            return oblist;  
        }  
      
      
      
      
        /// <summary>    
        /// 将集合类转换成DataTable    
        /// </summary>    
        /// <param name="list">集合</param>    
        /// <returns></returns>    
        public static DataTable ToDataTableTow(IList list)  
        {  
            DataTable result = new DataTable();  
            if (list.Count > 0)  
            {  
                PropertyInfo[] propertys = list[0].GetType().GetProperties();  
      
                foreach (PropertyInfo pi in propertys)  
                {  
                    result.Columns.Add(pi.Name, pi.PropertyType);  
                }  
                for (int i = 0; i < list.Count; i++)  
                {  
                    ArrayList tempList = new ArrayList();  
                    foreach (PropertyInfo pi in propertys)  
                    {  
                        object obj = pi.GetValue(list[i], null);  
                        tempList.Add(obj);  
                    }  
                    object[] array = tempList.ToArray();  
                    result.LoadDataRow(array, true);  
                }  
            }  
            return result;  
        }  
      
      
        /**/  
      
        /// <summary>    
        /// 将泛型集合类转换成DataTable    
      
        /// </summary>    
        /// <typeparam name="T">集合项类型</typeparam>    
      
        /// <param name="list">集合</param>    
        /// <returns>数据集(表)</returns>    
        public static DataTable ToDataTable<T>(IList<T> list)  
        {  
            return ToDataTable<T>(list, null);  
      
        }  
      
      
        /**/  
      
        /// <summary>    
        /// 将泛型集合类转换成DataTable    
        /// </summary>    
        /// <typeparam name="T">集合项类型</typeparam>    
        /// <param name="list">集合</param>    
        /// <param name="propertyName">需要返回的列的列名</param>    
        /// <returns>数据集(表)</returns>    
        public static DataTable ToDataTable<T>(IList<T> list, params string[] propertyName)  
        {  
            List<string> propertyNameList = new List<string>();  
            if (propertyName != null)  
                propertyNameList.AddRange(propertyName);  
            DataTable result = new DataTable();  
            if (list.Count > 0)  
            {  
                PropertyInfo[] propertys = list[0].GetType().GetProperties();  
                foreach (PropertyInfo pi in propertys)  
                {  
                    if (propertyNameList.Count == 0)  
                    {  
                        result.Columns.Add(pi.Name, pi.PropertyType);  
                    }  
                    else  
                    {  
                        if (propertyNameList.Contains(pi.Name))  
                            result.Columns.Add(pi.Name, pi.PropertyType);  
                    }  
                }  
      
                for (int i = 0; i < list.Count; i++)  
                {  
                    ArrayList tempList = new ArrayList();  
                    foreach (PropertyInfo pi in propertys)  
                    {  
                        if (propertyNameList.Count == 0)  
                        {  
                            object obj = pi.GetValue(list[i], null);  
                            tempList.Add(obj);  
                        }  
                        else  
                        {  
                            if (propertyNameList.Contains(pi.Name))  
                            {  
                                object obj = pi.GetValue(list[i], null);  
                                tempList.Add(obj);  
                            }  
                        }  
                    }  
                    object[] array = tempList.ToArray();  
                    result.LoadDataRow(array, true);  
                }  
            }  
            return result;  
        }  
    }  
View Code

 

posted @ 2016-01-14 09:10  山顶洞外人  阅读(180)  评论(0编辑  收藏  举报