用MVC4练习,后台用aspx，数据库DemoDb《MvcUserDemo》

  1 using System;
  2 using System.Collections.Generic;
  3 using System.Linq;
  4 using System.Text;
  5 using System.Configuration;
  6 using System.Data.SqlClient;
  7 using System.Data;
  8 
  9 namespace MvcUserDemo
 10 {
 11     public static class  SqlHelper
 12     {
 13         public static readonly string connstr =
 14             ConfigurationManager.ConnectionStrings["connstr"].ConnectionString;
 15 
 16         public static SqlConnection OpenConnection()
 17         {
 18             SqlConnection conn = new SqlConnection(connstr);
 19             conn.Open();
 20             return conn;
 21         }
 22 
 23         public static int ExecuteNonQuery(string cmdText,
 24             params SqlParameter[] parameters)
 25         {
 26             using (SqlConnection conn = new SqlConnection(connstr))
 27             {
 28                 conn.Open();
 29                 return ExecuteNonQuery(conn, cmdText, parameters);
 30             }
 31         }
 32 
 33         public static object ExecuteScalar(string cmdText,
 34             params SqlParameter[] parameters)
 35         {
 36             using (SqlConnection conn = new SqlConnection(connstr))
 37             {
 38                 conn.Open();
 39                 return ExecuteScalar(conn, cmdText, parameters);
 40             }
 41         }
 42 
 43         public static DataTable ExecuteDataTable(string cmdText,
 44             params SqlParameter[] parameters)
 45         {
 46             using (SqlConnection conn = new SqlConnection(connstr))
 47             {
 48                 conn.Open();
 49                 return ExecuteDataTable(conn, cmdText, parameters);
 50             }
 51         }
 52 
 53         public static int ExecuteNonQuery(SqlConnection conn,string cmdText,
 54            params SqlParameter[] parameters)
 55         {
 56             using (SqlCommand cmd = conn.CreateCommand())
 57             {
 58                 cmd.CommandText = cmdText;
 59                 cmd.Parameters.AddRange(parameters);
 60                 return cmd.ExecuteNonQuery();
 61             }
 62         }
 63 
 64         public static object ExecuteScalar(SqlConnection conn, string cmdText,
 65             params SqlParameter[] parameters)
 66         {
 67             using (SqlCommand cmd = conn.CreateCommand())
 68             {
 69                 cmd.CommandText = cmdText;
 70                 cmd.Parameters.AddRange(parameters);
 71                 return cmd.ExecuteScalar();
 72             }
 73         }
 74 
 75         public static DataTable ExecuteDataTable(SqlConnection conn, string cmdText,
 76             params SqlParameter[] parameters)
 77         {
 78             using (SqlCommand cmd = conn.CreateCommand())
 79             {
 80                 cmd.CommandText = cmdText;
 81                 cmd.Parameters.AddRange(parameters);
 82                 using (SqlDataAdapter adapter = new SqlDataAdapter(cmd))
 83                 {
 84                     DataTable dt = new DataTable();
 85                     adapter.Fill(dt);
 86                     return dt;
 87                 }
 88             }
 89         }
 90 
 91         public static object ToDBValue(this object value)
 92         {
 93             return value == null ? DBNull.Value : value;
 94         }
 95 
 96         public static object FromDBValue(this object dbValue)
 97         {
 98             return dbValue == DBNull.Value ? null : dbValue;
 99         }
100     }
101 }