c#连接sql数据库并调用

标签：c#   dataset   数据库   sql   

1、导入命名空间
  using System.Data.SqlClient;  //连接SQLServer 数据库专用

2、创建连接
  SqlConnection lo_conn = New SqlConnection("Server=服务器名字或IP;Database=数据库名字;uid=用户名;pwd=密码");

3、打开连接，第2步并没有真正连接数据库
  lo_conn.Open();    //真正与数据库连接

4、向数据库发送SQL命令要使用SqlCommand:
  SqlCommand lo_cmd = new SqlCommand();   //创建命令对象
  lo_cmd.CommandText = "这里是SQL语句";   //写SQL语句
  lo_cmd.Connection = lo_con;             //指定连接对象，即上面创建的

5、处理SQL命令或返回结果集
  lo_cmd.ExecuteNonQuery();  //这个仅仅执行SQL命令，不返回结果集，实用于建表、批量更新等不需要返回结果的操作。
  SqlDataReader lo_reader = lo_cmd.ExecuteReader();//返回结果集

6、以数据集的方式反回结果集
  SqlDataAdapter dbAdapter = new SqlDataAdapter(lo_cmd); //注意与上面的区分开
  DataSet ds = new DataSet(); //创建数据集对象
  dbAdapter.Fill(ds); //用返回的结果集填充数据集，这个数据集可以被能操作数据的控件DataBind,其它的就自己发挥了吧

7、关闭连接
  lo_conn.Close();

    /// <summary>
    /// 数据库操作处理器
    /// </summary>
    public class SQLProcessor
    {
        private SqlConnection conn;
        public SqlConnection Conn
        {
            get
            {
                if (conn == null)
                {
                    conn = ConnUtil.CreateConnection();//此处直接是一个连接串："Initial Catalog=TOPJOIN;Data Source=130.1.0.15;User ID=sa;Password=topdj@123;Connect Timeout=30"
                }
                return conn;
            }
            set
            {
                conn = value;
            }
        }     

        /// <summary>
        /// 执行sql
        /// </summary>
        /// <param name="sql"></param>
        /// <param name="parameters"></param>
        /// <returns></returns>
        public DataSet ExecuteQuery(string sql, SqlParameter[] parameters)
        {
            DataSet ds = new DataSet();
            Conn.Open();
            SqlCommand sc = new SqlCommand(sql, conn);
            sc.Transaction = Conn.BeginTransaction();
            try
            {
                if (!BaseUtil.isArrayEmpty(parameters))
                {
                    sc.Parameters.AddRange(parameters);
                }
                SqlDataAdapter command = new SqlDataAdapter(sc);

                command.Fill(ds);
            }
            catch (Exception e)
            {
                if (sc != null && sc.Transaction != null)
                    sc.Transaction.Rollback();
                if (Conn != null)
                    Conn.Close();
                throw new Exception(e.Message);
            }
            finally
            {
                if (sc != null && sc.Transaction != null)
                    sc.Transaction.Commit();
                if (Conn != null)
                    Conn.Close();
            }
            return ds;
        }

        /// <summary>
        /// 执行存储过程
        /// </summary>
        /// <param name="spname"></param>
        /// <param name="parameters"></param>
        /// <returns></returns>
        public DataSet ExecuteStoredProcedure(string spname, SqlParameter[] parameters)
        {
            DataSet ds = new DataSet();
            Conn.Open();
            SqlCommand cmd = new SqlCommand();
            cmd.CommandType = CommandType.StoredProcedure;//设置cmd的类型为存储过程     
            cmd.CommandText = spname;
            cmd.Connection = conn;
            try
            {
                if (!BaseUtil.isArrayEmpty(parameters))
                {
                    cmd.Parameters.AddRange(parameters);
                }
                SqlDataAdapter command = new SqlDataAdapter(cmd);

                command.Fill(ds);
            }
            catch (Exception e)
            {
                if (Conn != null)
                    Conn.Close();
                throw new Exception(e.Message);
            }
            finally
            {
                if (cmd != null && cmd.Transaction != null)
                    cmd.Transaction.Commit();
                if (Conn != null)
                    Conn.Close();
            }
            return ds;
        }

<span style="white-space:pre">	</span>    string sql = " select * from User where code = @Code ";
            List<SqlParameter> lsp = new List<SqlParameter>();
            lsp.Add(new SqlParameter("Code", code));//code为参数值哈
            SQLProcessor sp = new SQLProcessor();
            DataSet ds = sp.ExecuteQuery(sql, lsp.ToArray()) as DataSet;

<span style="white-space:pre">	</span>    StringBuilder sb = new StringBuilder();
            sb.Append(" select * from User ");
            sb.Append(string.Format(" where code ='{0}' ",new String[]{code}));//code为参数值哈
            SQLProcessor sp = new SQLProcessor();
            DataSet ds = sp.ExecuteQuery(sb.ToString(),null) as DataSet;

c#连接sql数据库并调用

标签：c#   dataset   数据库   sql   

原文地址：http://blog.csdn.net/ychxiaoyixiao/article/details/46602691