MVC-EF数据操作（一）

EF数据操作

　　新建一个类库，命名为DBUtility

DbHelper类

　　该类主要执行各种SQL语句，定义一个私有的string类型数据库连接串conStr，在构造里面给其赋值

1         /// <summary>

2         /// 数据库连接串

3         /// </summary>

4         private string conStr;// = ConfigurationManager.ConnectionStrings["DbConStr"].ConnectionString;

5 

6         public DbHelper(string dbConStr)

7         {

8             conStr = dbConStr;

9         }

　　执行简单的SQL语句的各个方法

  1         /// <summary>

  2         /// 返回DataTable

  3         /// </summary>

  4         /// <param name="strSql"></param>

  5         /// <returns></returns>

  6         public DataTable GetDataTable(string strSql)

  7         {

  8             try

  9             {

 10                 using (SqlConnection con = new SqlConnection(conStr))

 11                 {

 12                     DataSet ds = new DataSet();

 13                     SqlDataAdapter da = new SqlDataAdapter(strSql, con);

 14                     da.Fill(ds);

 15                     return ds.Tables[0];

 16                 }

 17             }

 18             catch (Exception ex)

 19             {

 20                 return null;

 21                 throw ex;

 22             }

 23         }

 24 

 25         /// <summary>

 26         /// 执行sql,返回受影响的行数

 27         /// </summary>

 28         /// <param name="strSql"></param>

 29         /// <returns></returns>

 30         public bool ExecuteSql(string strSql)

 31         {

 32             try

 33             {

 34                 using (SqlConnection con = new SqlConnection(conStr))

 35                 {

 36                     SqlCommand command = new SqlCommand(strSql, con);

 37                     con.Open();

 38                     return command.ExecuteNonQuery() > 0;

 39                 }

 40             }

 41             catch

 42             {

 43                 return false;

 44             }

 45         }

 46 

 47         /// <summary>

 48         /// 执行SQL命令

 49         /// </summary>

 50         /// <param name="cmd"></param>

 51         /// <returns></returns>

 52         public int ExecuteCommand(SqlCommand cmd)

 53         {

 54             try

 55             {

 56                 using (SqlConnection con = new SqlConnection(conStr))

 57                 {

 58                     cmd.Connection = con;

 59                     con.Open();

 60                     return cmd.ExecuteNonQuery();

 61                 }

 62             }

 63             catch

 64             {

 65                 return -1;

 66             }

 67         }

 68 

 69         /// <summary>

 70         /// 执行sql,返回首行首列

 71         /// </summary>

 72         /// <param name="strSql"></param>

 73         /// <returns></returns>

 74         public object ExecuteScalar(string strSql)

 75         {

 76             try

 77             {

 78                 using (SqlConnection con = new SqlConnection(conStr))

 79                 {

 80                     SqlCommand command = new SqlCommand(strSql, con);

 81                     con.Open();

 82                     return command.ExecuteScalar();

 83                 }

 84             }

 85             catch (Exception ex)

 86             {

 87                 throw ex;

 88             }

 89         }

 90 

 91         /// <summary>

 92         /// 执行事务

 93         /// </summary>

 94         /// <param name="sqlStrList"></param>

 95         /// <returns></returns>

 96         public bool ExecuteSqlTran(List<string> sqlStrList)

 97         {

 98             try

 99             {

100                 using (SqlConnection con = new SqlConnection(conStr))

101                 {

102                     con.Open();

103                     using (SqlTransaction sqlTransaction = con.BeginTransaction())

104                     {

105                         try

106                         {

107                             foreach (string sqlStr in sqlStrList)

108                             {

109                                 SqlCommand command = new SqlCommand(sqlStr, con);

110                                 command.Transaction = sqlTransaction;

111                                 command.ExecuteNonQuery();

112                             }

113                             sqlTransaction.Commit();

114                             return true;

115                         }

116                         catch (Exception transEx)

117                         {

118                             sqlTransaction.Rollback();

119                             return false;

120                             throw transEx;

121                         }

122                     }

123                 }

124             }

125             catch (Exception ex)

126             {

127                 return false;

128                 throw ex;

129             }

130         }

View Code

　　执行带参数的SQL语句的方法

 1         /// <summary>

 2         ///  返回DataTable

 3         /// </summary>

 4         /// <param name="str"></param>

 5         /// <param name="values"></param>

 6         /// <returns></returns>

 7         public DataTable GetDataTable(string str, params SqlParameter[] values)

 8         {

 9             try

10             {

11                 using (SqlConnection con = new SqlConnection(conStr))

12                 {

13                     DataSet ds = new DataSet();

14                     SqlCommand command = new SqlCommand(str, con);

15                     command.Parameters.AddRange(values);

16                     SqlDataAdapter da = new SqlDataAdapter(command);

17                     da.Fill(ds);

18                     return ds.Tables[0];

19                 }

20             }

21             catch (Exception ex)

22             {

23                 return null;

24                 throw ex;

25             }

26         }

27 

28         /// <summary>

29         /// 执行多条SQL语句，实现数据库事务。

30         /// </summary>

31         /// <param name="sqlDic"></param>

32         public void ExecuteSqlTran(Dictionary<string, SqlParameter[]> sqlDic)

33         {

34             using (SqlConnection conn = new SqlConnection(conStr))

35             {

36                 conn.Open();

37                 using (SqlTransaction trans = conn.BeginTransaction())

38                 {

39                     SqlCommand cmd = new SqlCommand();

40                     try

41                     {

42                         //循环

43                         foreach (var dic in sqlDic)

44                         {

45                             SqlCommand command = new SqlCommand(dic.Key, conn);

46                             if (dic.Value != null)

47                             {

48                                 command.Parameters.AddRange(dic.Value);

49                             }

50                             command.Transaction = trans;

51                             command.ExecuteNonQuery();

52                         }

53                         trans.Commit();

54                     }

55                     catch

56                     {

57                         trans.Rollback();

58                         throw;

59                     }

60                 }

61             }

62         }

View Code