sqlHelper

Question

 帮我写这个类，参数只要sql语句。

Answer 1

.........
下载petshop里面就有

Answer 2

using System;
using System.Data;
using System.Configuration;
using System.Web;
using System.Collections;
using System.Data.SqlClient;namespace DAL
{
    public abstract class SqlHelper
    {
        //获取数据库连接字符串，其属于静态变量且只读，项目中所有文档可以直接使用，但不能修改
        public static readonly string ConnectionStringLocalTransaction = ConfigurationManager.ConnectionStrings["MyBookShop"].ConnectionString;        // 哈希表用来存储缓存的参数信息，哈希表可以存储任意类型的参数。
        private static Hashtable parmCache = Hashtable.Synchronized(new Hashtable());
        public static int ExecuteNonQuery(string connectionString, CommandType cmdType, string cmdText, params SqlParameter[] commandParameters)
        {            SqlCommand cmd = new SqlCommand();            using (SqlConnection conn = new SqlConnection(connectionString))
            {
                PrepareCommand(cmd, conn, null, cmdType, cmdText, commandParameters);
                int val = cmd.ExecuteNonQuery();
                cmd.Parameters.Clear();
                return val;
            }
        }
        public static int ExecuteNonQuery(SqlConnection connection, CommandType cmdType, string cmdText, params SqlParameter[] commandParameters)
        {            SqlCommand cmd = new SqlCommand();            PrepareCommand(cmd, connection, null, cmdType, cmdText, commandParameters);
            int val = cmd.ExecuteNonQuery();
            cmd.Parameters.Clear();
            return val;
        }
        public static int ExecuteNonQuery(SqlTransaction trans, CommandType cmdType, string cmdText, params SqlParameter[] commandParameters)
        {
            SqlCommand cmd = new SqlCommand();
            PrepareCommand(cmd, trans.Connection, trans, cmdType, cmdText, commandParameters);
            int val = cmd.ExecuteNonQuery();
            cmd.Parameters.Clear();
            return val;
        }
        public static SqlDataReader ExecuteReader(string connectionString, CommandType cmdType, string cmdText, params SqlParameter[] commandParameters)
        {
            SqlCommand cmd = new SqlCommand();
            SqlConnection conn = new SqlConnection(connectionString);
            try
            {
                PrepareCommand(cmd, conn, null, cmdType, cmdText, commandParameters);
                SqlDataReader rdr = cmd.ExecuteReader(CommandBehavior.CloseConnection);
                cmd.Parameters.Clear();
                return rdr;
            }
            catch
            {
                conn.Close();
                throw;
            }
        }
        public static object ExecuteScalar(string connectionString, CommandType cmdType, string cmdText, params SqlParameter[] commandParameters)
        {
            SqlCommand cmd = new SqlCommand();            using (SqlConnection connection = new SqlConnection(connectionString))
            {
                PrepareCommand(cmd, connection, null, cmdType, cmdText, commandParameters);
                object val = cmd.ExecuteScalar();
                cmd.Parameters.Clear();
                return val;
            }
        }
        public static object ExecuteScalar(SqlConnection connection, CommandType cmdType, string cmdText, params SqlParameter[] commandParameters)
        {            SqlCommand cmd = new SqlCommand();            PrepareCommand(cmd, connection, null, cmdType, cmdText, commandParameters);
            object val = cmd.ExecuteScalar();
            cmd.Parameters.Clear();
            return val;
        }
        public static void CacheParameters(string cacheKey, params SqlParameter[] commandParameters)
        {
            parmCache[cacheKey] = commandParameters;
        }
        public static SqlParameter[] GetCachedParameters(string cacheKey)
        {
            SqlParameter[] cachedParms = (SqlParameter[])parmCache[cacheKey];            if (cachedParms == null)
                return null;
            SqlParameter[] clonedParms = new SqlParameter[cachedParms.Length];
            for (int i = 0, j = cachedParms.Length; i < j; i++)
                clonedParms[i] = (SqlParameter)((ICloneable)cachedParms[i]).Clone();            return clonedParms;
        }
        private static void PrepareCommand(SqlCommand cmd, SqlConnection conn, SqlTransaction trans, CommandType cmdType, string cmdText, SqlParameter[] cmdParms)
        {
            if (conn.State != ConnectionState.Open)
                conn.Open();            cmd.Connection = conn;
            cmd.CommandText = cmdText;
            if (trans != null)
                cmd.Transaction = trans;            cmd.CommandType = cmdType;            if (cmdParms != null)
            {
                foreach (SqlParameter parm in cmdParms)
                    cmd.Parameters.Add(parm);
            }
        }
    }
}

Answer 3

看看petshop或到51aaspx.com里看看，很多
 public static DataTable ExecuteDt(String Sqlstr)
    {
        String ConnStr = DbHelper.GetSqlConnection();
        using (OleDbConnection conn = new OleDbConnection(ConnStr))
        {
            SqlDataAdapter da = new SqlDataAdapter(Sqlstr, conn);
            DataTable dt = new DataTable();
            conn.Open();
            da.Fill(dt);
            conn.Close();
            return dt;
        }
    }public static class DBHelper
    {
        private static SqlConnection connection;
        public static SqlConnection Connection
        {
            get 
            {
                string connectionString = ConfigurationManager.ConnectionStrings["ConnectionString"].ConnectionString;
                if (connection == null)
                {
                    connection = new SqlConnection(connectionString);
                    connection.Open();
                }
                else if (connection.State == System.Data.ConnectionState.Closed)
                {
                    connection.Open();
                }
                else if (connection.State == System.Data.ConnectionState.Broken)
                {
                    connection.Close();
                    connection.Open();
                }
                return connection;
            }
        }
        public static int ExecuteCommand(string Sql)
        {
            SqlCommand cmd = new SqlCommand(Sql, Connection);
            int result = cmd.ExecuteNonQuery();
            return result;
        }        public static int ExecuteCommand(string sql, params SqlParameter[] values)
        {
            SqlCommand cmd = new SqlCommand(sql, Connection);
            cmd.Parameters.AddRange(values);
            return cmd.ExecuteNonQuery();
        }        public static int GetScalar(string Sql)
        {
            SqlCommand cmd = new SqlCommand(Sql, Connection);
            int result = Convert.ToInt32(cmd.ExecuteScalar());
            return result;
        }        public static SqlDataReader GetReader(string Sql)
        {
            SqlCommand cmd = new SqlCommand(Sql, Connection);
            SqlDataReader reader = cmd.ExecuteReader(CommandBehavior.CloseConnection);
            return reader;
        }
        public static DataTable GetDataSet(string Sql)
        {
            DataSet ds = new DataSet();
            SqlCommand cmd = new SqlCommand(Sql, Connection);
            SqlDataAdapter da = new SqlDataAdapter(cmd);
            da.Fill(ds);
            return ds.Tables[0];
        }
    }

Answer 4

下载个sqlhelper
对ms sql万事ok哦