using System.Web.Script.Serialization;using System.Collections.Generic;using System.Reflection;using System.Data;using System;namespace CommonCode{    public class Common    {        /// 
         /// LINQ返回DataTable类型        /// 
         public static DataTable ToDataTable
     
      (IEnumerable
      
        varlist)        {            DataTable dtReturn = new DataTable();            // column names             PropertyInfo[] oProps = null;            if (varlist == null)                return dtReturn;            foreach (T rec in varlist)            {                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;        }        /// 
       
        /// list转dataset        /// 
        public static DataSet ConvertToDataSet
       
        (IList
        
          list)        {            if (list == null || list.Count <= 0)                return null;            DataSet ds = new DataSet();            DataTable dt = new DataTable(typeof(T).Name);            DataColumn column;            DataRow row;            System.Reflection.PropertyInfo[] myPropertyInfo =                typeof(T).GetProperties(System.Reflection.BindingFlags.Public | System.Reflection.BindingFlags.Instance);            foreach (T t in list)            {                if (t == null) continue;                row = dt.NewRow();                for (int i = 0, j = myPropertyInfo.Length; i < j; i++)                {                    System.Reflection.PropertyInfo pi = myPropertyInfo[i];                    String name = pi.Name;                    if (dt.Columns[name] == null)                    {                        if (pi.PropertyType.UnderlyingSystemType.ToString() == "System.Nullable`1[System.Int32]")                        {                            column = new DataColumn(name, typeof(Int32));                            dt.Columns.Add(column);                            //row[name] = pi.GetValue(t, new object[] {i});//PropertyInfo.GetValue(object,object[])                            if (pi.GetValue(t, null) != null)                                row[name] = pi.GetValue(t, null);                            else                                row[name] = System.DBNull.Value;                        }                        else if (pi.PropertyType.UnderlyingSystemType.ToString() == "System.Nullable`1[System.DateTime]")                        {                            column = new DataColumn(name, typeof(DateTime));                            dt.Columns.Add(column);                            if (pi.GetValue(t, null) != null)                                row[name] = pi.GetValue(t, null);                            else                                row[name] = System.DBNull.Value;                        }                        else                        {                            column = new DataColumn(name, pi.PropertyType);                            dt.Columns.Add(column);                            row[name] = pi.GetValue(t, null);                        }                    }                }                dt.Rows.Add(row);            }            ds.Tables.Add(dt);            return ds;        }        public delegate object[] CreateRowDelegate
         
          (T t);        public static string Serialize(DataTable dt)        {            List
          
           
            > list = new List
            
             
              >(); foreach (DataRow dr in dt.Rows) { Dictionary
              
                result = new Dictionary
               
                (); foreach (DataColumn dc in dt.Columns) { result.Add(dc.ColumnName, dr[dc].ToString()); } list.Add(result); } int count = 0; try { count = Convert.ToInt32(dt.TableName); } catch (System.Exception ex) { count = dt.Rows.Count; } string strReturn = ""; if (count == 0) { strReturn = "{\"totalCount\":0,\"data\":[]}"; } else { strReturn = ConventToJson(list, count); } return strReturn; } /// 
                
 /// 转换为JSON对象 /// 
 public static string ConventToJson
                
                 (List
                 
                   list, int count) { JavaScriptSerializer serializer = new JavaScriptSerializer(); string strJson = serializer.Serialize(list); strJson = strJson.Substring(1); strJson = strJson.Insert(0, "{totalCount:" + count + ",data:["); strJson += "}"; return strJson; } /// 
                  
 /// 不需要分页 /// 
 public static string Serialize(DataTable dt, bool flag) { JavaScriptSerializer serializer = new JavaScriptSerializer(); List
                  
                   
                    > list = new List
                    
                     
                      >(); foreach (DataRow dr in dt.Rows) { Dictionary
                      
                        result = new Dictionary
                       
                        (); foreach (DataColumn dc in dt.Columns) { result.Add(dc.ColumnName, dr[dc].ToString()); } list.Add(result); } return serializer.Serialize(list); } }}