青鸟 王云鹏老师写的SqlHelper 泛型方法，反射，支持实体类

  1: using System;

  2: using System.Collections.Generic;

  3: using System.Linq;

  4: using System.Text;

  5: using System.Data;

  6: using System.Data.SqlClient;

  7: using System.Reflection;

  8:

  9: namespace DAL

 10: {

 11:     public class SqlHelper

 12:     {

 13:         private const string CONNECTION_STRING = @"server=.\sql2008;uid=sa;pwd=;database=BBSDB";

 14:

 15:         private static T ExecuteReader<T>(SqlDataReader dr)

 16:         {

 17:             T obj = default(T);

 18:             obj = Activator.CreateInstance<T>();//T obj = new T();//instance

 19:             Type type = typeof(T);//get T class type by T's Name

 20:             PropertyInfo[] propertyInfos = type.GetProperties();//get current Type's all properties

 21:             int fieldCount = dr.FieldCount;//get column count

 22:             for (int i = 0; i < fieldCount; i++)

 23:             {

 24:                 string fieldName = dr.GetName(i);//get column

 25:                 foreach (PropertyInfo propertyInfo in propertyInfos)

 26:                 {//per property infoname

 27:                     string properyName = propertyInfo.Name;//get property name

 28:                     if (string.Compare(fieldName, properyName, true) == 0)

 29:                     {//column's name == propery's name

 30:                         object value = dr.GetValue(i);//get column's value

 31:                         if (value != null && value != DBNull.Value)

 32:                         {

 33:                             propertyInfo.SetValue(obj, value, null);//set property's value

 34:                         }

 35:                         break;

 36:                     }

 37:                 }

 38:             }

 39:             return obj;

 40:         }

 41:

 42:         public static List<T> ExecuteList<T>(string cmdText, CommandType commandType, params SqlParameter[] args)

 43:         {

 44:             List<T> list = new List<T>();

 45:             using (SqlConnection con = new SqlConnection(CONNECTION_STRING))

 46:             {

 47:                 using (SqlCommand cmd = new SqlCommand(cmdText, con))

 48:                 {

 49:                     cmd.CommandType = commandType;

 50:                     cmd.Parameters.AddRange(args);

 51:                     con.Open();

 52:                     using (SqlDataReader dr = cmd.ExecuteReader(CommandBehavior.CloseConnection))

 53:                     {

 54:                         while (dr.Read())

 55:                         {

 56:                             //dr.GetInt32(0);

 57:                             //dr.GetString(1);

 58:                             T obj = ExecuteReader<T>(dr);

 59:                             list.Add(obj);

 60:                         }

 61:                     }

 62:                 }

 63:             }

 64:             return list;

 65:         }

 66:

 67:         public static T ExecuteEntity<T>(string cmdText, CommandType commandType, params SqlParameter[] args)

 68:         {

 69:             T obj = default(T);

 70:             using (SqlConnection con = new SqlConnection(CONNECTION_STRING))

 71:             {

 72:                 using (SqlCommand cmd = new SqlCommand(cmdText, con))

 73:                 {

 74:                     cmd.CommandType = commandType;

 75:                     cmd.Parameters.AddRange(args);

 76:                     con.Open();

 77:                     using (SqlDataReader dr = cmd.ExecuteReader(CommandBehavior.CloseConnection))

 78:                     {

 79:                         while (dr.Read())

 80:                         {

 81:                             obj = ExecuteReader<T>(dr);

 82:                             break;

 83:                         }

 84:                     }

 85:                 }

 86:             }

 87:             return obj;

 88:         }

 89:

 90:         public static int ExecuteNonQuery(string cmdText, CommandType commandType, params SqlParameter[] args)

 91:         {

 92:             int result = -1;

 93:             using (SqlConnection con = new SqlConnection(CONNECTION_STRING))

 94:             {

 95:                 using (SqlCommand cmd = new SqlCommand(cmdText, con))

 96:                 {

 97:                     cmd.Parameters.AddRange(args);

 98:                     cmd.CommandType = CommandType.StoredProcedure;

 99:                     con.Open();

100:                     result = cmd.ExecuteNonQuery();

101:                 }

102:             }

103:             return result;

104:         }

105:

106:     }

107: }

108: