自学.net(1)手写一个sqlhelper类
自学.net已经快一个月了,看的是传智播客的视频,今天正好申请了博客,就先把手写的sqlhelper类上传上去吧
别忘了在解决方案管理器的“引用”添加System.Configuration
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 SH 10 { 11 class SqlHelper 12 { 13 private static string connStr = ConfigurationManager.ConnectionStrings["dbConnStr"]
.ConnectionString; 14 15 16 public static int ExecuteNonQuery(string sql,params SqlParameter[] parameters) 17 { 18 using (SqlConnection conn = new SqlConnection(connStr)) 19 { 20 conn.Open(); 21 using (SqlCommand cmd = conn.CreateCommand()) 22 { 23 cmd.CommandText = sql; 24 //foreach (SqlParameter param in parameters) 25 //{ 26 // cmd.Parameters.Add(param); 27 //} 28 cmd.Parameters.AddRange(parameters); 29 return cmd.ExecuteNonQuery(); 30 } 31 } 32 } 33 34 public static object ExecuteScalar(string sql, params SqlParameter[] parameters) 35 { 36 using (SqlConnection conn = new SqlConnection(connStr)) 37 { 38 conn.Open(); 39 using (SqlCommand cmd = conn.CreateCommand()) 40 { 41 cmd.CommandText = sql; 42 cmd.Parameters.AddRange(parameters); 43 return cmd.ExecuteScalar(); 44 } 45 } 46 } 47 48 //只用来执行查询结果比较少的sql 49 public static DataTable ExecuteDataTable(string sql, params SqlParameter[] parameters) 50 { 51 using (SqlConnection conn = new SqlConnection(connStr)) 52 { 53 conn.Open(); 54 using (SqlCommand cmd = conn.CreateCommand()) 55 { 56 cmd.CommandText = sql; 57 cmd.Parameters.AddRange(parameters); 58 59 SqlDataAdapter adapter = new SqlDataAdapter(cmd); 60 DataSet dataset = new DataSet(); 61 adapter.Fill(dataset); 62 return dataset.Tables[0]; 63 } 64 } 65 } 66 } 67 }