SQL连接类

最新推荐文章于 2020-08-14 15:04:11 发布
原创 最新推荐文章于 2020-08-14 15:04:11 发布 · 321 阅读 · 0 ·
CC 4.0 BY-SA版权
版权声明：本文为博主原创文章，遵循 CC 4.0 BY-SA 版权协议，转载请附上原文出处链接和本声明。
文章标签：

#sql #dataset #parameters #exception #string #object

本文介绍了一个.NET框架下的数据访问层实现，包括数据库连接配置、基本SQL操作、存储过程调用及事务处理等核心功能。

using System;
using System.Collections;
using System.Collections.Specialized;
using System.Collections.Generic;
using System.Text;
using System.Data;
using System.Data.SqlClient;
using System.Configuration;
using System.Runtime.InteropServices;
using System.Windows.Forms;

namespace DAL
{
    public class DataControl
    {
        public static string connectionString = "server=" + SystemSet.getServerSet_ServerIP() + ";uid=" + SystemSet.getServerSet_ServerUser() + ";pwd=" + SystemSet.getServerSet_ServerPass() + ";database=" + SystemSet.getServerSet_ServerDataBase() + "";
        /// <summary>
        /// 初始化        /// </summary>
        public DataControl()
        {
        }
        /// <summary>
        /// 无参数，测试数据库连接是否设置合理。        /// </summary>
        /// <returns>是否连接成功</returns>
        public static bool checkconn()
        {
            try
            {
                SqlConnection conn = new SqlConnection(connectionString);
                conn.Open();
                return true;
            }
            catch (Exception)
            {
               //MessageBox.Show ( e.ToString());
                //MessageBox.Show(connectionString + "/r/n" + e.Message);
                return false;
            }
        }
        /// <summary>
        /// 1参数，测试数据库连接是否设置合理。   /// </summary>
        /// <param name="sqlstring">连接字符串</param>
        /// <returns>是否连接成功</returns>
        public static bool checkconn(string sqlstring)
        {
            connectionString = sqlstring;
            try
            {
                SqlConnection conn = new SqlConnection(connectionString);
                conn.Open();
                return true;
            }
            catch(Exception e)
            {
                MessageBox.Show(connectionString + "/r/n" + e.Message);
                return false;
            }
        }
        /// <summary>
        /// 查询返回首行第一个字段值        /// </summary>
        /// <param name="query"></param>
        /// <param name="paras"></param>
        /// <returns></returns>
        public static object executeScaler(string query, SqlParameter[] paras)
        {
            using (SqlConnection connection = new SqlConnection(connectionString))
            {
                try
                {
                    SqlCommand cmd = new SqlCommand();
                    cmd.Connection = connection;
                    cmd.CommandType = CommandType.StoredProcedure;
                    cmd.CommandText = query;
                    connection.Open();
                    object id = Convert.ToInt32(cmd.ExecuteScalar());
                    connection.Close();
                    return id;
                   
                }
                catch (SqlException e)
                {
                    connection.Close();
                    throw new Exception(e.ToString ());
                }           
            }
        }

 

        //private Check
        #region 公用方法
        //public string server,uid,pwd,database;

        public static int GetMaxID(string FieldName, string TableName)
        {
            string strsql = "select max(" + FieldName + ")+1 from " + TableName;
            object obj = GetSingle(strsql);
            if (obj == null)
            {
                return 1;
            }
            else
            {
                return int.Parse(obj.ToString());
            }
        }
        public static bool Exists(string strSql, params SqlParameter[] cmdParms)
        {
            object obj = GetSingle(strSql, cmdParms);
            int cmdresult;
            if ((Object.Equals(obj, null)) || (Object.Equals(obj, System.DBNull.Value)))
            {
                cmdresult = 0;
            }
            else
            {
                cmdresult = int.Parse(obj.ToString());
            }
            if (cmdresult == 0)
            {
                return false;
            }
            else
            {
                return true;
            }
        }
        #endregion

        #region  执行简单SQL语句

        /**/
        /// <summary>
        /// 执行SQL语句，返回影响的记录数

 

 

        /// </summary>
        /// <param name="SQLString">SQL语句</param>
        /// <returns>影响的记录数</returns>
        public static int ExecuteSql(string SQLString)
        {
            using (SqlConnection connection = new SqlConnection(connectionString))
            {
                using (SqlCommand cmd = new SqlCommand(SQLString, connection))
                {
                    try
                    {
                        connection.Open();
                        int rows = cmd.ExecuteNonQuery();
                        return rows;
                    }
                    catch (System.Data.SqlClient.SqlException E)
                    {
                        connection.Close();
                        throw new Exception(E.Message);
                    }
                }
            }
        }

        /**/
        /// <summary>
        /// 执行多条SQL语句，实现数据库事务。

 

 

        /// </summary>
        /// <param name="SQLStringList">多条SQL语句</param> 
        public static void ExecuteSqlTran(ArrayList SQLStringList)
        {
            using (SqlConnection conn = new SqlConnection(connectionString))
            {
                conn.Open();
                SqlCommand cmd = new SqlCommand();
                cmd.Connection = conn;
                SqlTransaction tx = conn.BeginTransaction();
                cmd.Transaction = tx;
                try
                {
                    for (int n = 0; n < SQLStringList.Count; n++)
                    {
                        string strsql = SQLStringList[n].ToString();
                        if (strsql.Trim().Length > 1)
                        {
                            cmd.CommandText = strsql;
                            cmd.ExecuteNonQuery();
                        }
                    }
                    tx.Commit();
                }
                catch (System.Data.SqlClient.SqlException E)
                {
                    tx.Rollback();
                    throw new Exception(E.Message);
                }
            }
        }
        /**/
        /// <summary>
        /// 执行带一个存储过程参数的的SQL语句。

 

 

        /// </summary>
        /// <param name="SQLString">SQL语句</param>
        /// <param name="content">参数内容,比如一个字段是格式复杂的文章，有特殊符号，可以通过这个方式添加</param>
        /// <returns>影响的记录数</returns>
        public static int ExecuteSql(string SQLString, string content)
        {

            using (SqlConnection connection = new SqlConnection(connectionString))
            {
                SqlCommand cmd = new SqlCommand(SQLString, connection);
                System.Data.SqlClient.SqlParameter myParameter = new System.Data.SqlClient.SqlParameter("@content", SqlDbType.NText);
                myParameter.Value = content;
                cmd.Parameters.Add(myParameter);
                try
                {
                    connection.Open();
                    int rows = cmd.ExecuteNonQuery();
                    return rows;
                }
                catch (System.Data.SqlClient.SqlException E)
                {
                    throw new Exception(E.Message);
                }
                finally
                {
                    cmd.Dispose();
                    connection.Close();
                }
            }
        }
        /**/
        /// <summary>
        /// 向数据库里插入图像格式的字段(和上面情况类似的另一种实例)
        /// </summary>
        /// <param name="strSQL">SQL语句</param>
        /// <param name="fs">图像字节,数据库的字段类型为image的情况</param>
        /// <returns>影响的记录数</returns>
        public static int ExecuteSqlInsertImg(string strSQL, byte[] fs)
        {
            using (SqlConnection connection = new SqlConnection(connectionString))
            {
                SqlCommand cmd = new SqlCommand(strSQL, connection);
                System.Data.SqlClient.SqlParameter myParameter = new System.Data.SqlClient.SqlParameter("@fs", SqlDbType.Image);
                myParameter.Value = fs;
                cmd.Parameters.Add(myParameter);
                try
                {
                    connection.Open();
                    int rows = cmd.ExecuteNonQuery();
                    return rows;
                }
                catch (System.Data.SqlClient.SqlException E)
                {
                    throw new Exception(E.Message);
                }
                finally
                {
                    cmd.Dispose();
                    connection.Close();
                }
            }
        }

        /**/
        /// <summary>
        /// 执行一条计算查询结果语句，返回查询结果（object）。

 


 /// </summary>
        /// <param name="SQLString">计算查询结果语句</param>
        /// <returns>查询结果（object）</returns>
        public static object GetSingle(string SQLString)
        {
            //if (!checksqlstring())
            //{
            //    MessageBox.Show("数据库连接错误！");
            //    return null; ;
            //}
            using (SqlConnection connection = new SqlConnection(connectionString))
            {
                using (SqlCommand cmd = new SqlCommand(SQLString, connection))
                {
                    try
                    {
                        connection.Open();
                        object obj = cmd.ExecuteScalar();
                        if ((Object.Equals(obj, null)) || (Object.Equals(obj, System.DBNull.Value)))
                        {
                            return null;
                        }
                        else
                        {
                            return obj;
                        }
                    }
                    catch (System.Data.SqlClient.SqlException e)
                    {
                        connection.Close();
                        throw new Exception(e.Message);
                    }
                }
            }
        }
        /**/
        /// <summary>
        /// 执行查询语句，返回SqlDataReader
        /// </summary>
        /// <param name="strSQL">查询语句</param>
        /// <returns>SqlDataReader</returns>
        public static SqlDataReader ExecuteReader(string strSQL)
        {
            SqlConnection connection = new SqlConnection(connectionString);
            SqlCommand cmd = new SqlCommand(strSQL, connection);
            try
            {
                connection.Open();
                SqlDataReader myReader = cmd.ExecuteReader();
                return myReader;
            }
            catch (System.Data.SqlClient.SqlException e)
            {
                throw new Exception(e.Message);
            }

        }
        /**/
        /// <summary>
        /// 执行查询语句，返回DataSet
        /// </summary>
        /// <param name="SQLString">查询语句</param>
        /// <returns>DataSet</returns>
        public static DataSet Query(string SQLString)
        {

            using (SqlConnection connection = new SqlConnection(connectionString))
            {
                DataSet ds = new DataSet();
                try
                {
                    connection.Open();
                    SqlDataAdapter command = new SqlDataAdapter(SQLString, connection);
                    command.Fill(ds, "ds");
                }
                catch (System.Data.SqlClient.SqlException ex)
                {
                    throw new Exception(ex.Message);
                }
                return ds;
            }
        }


        #endregion

        #region 执行带参数的SQL语句

        /**/
        /// <summary>
        /// 执行SQL语句，返回影响的记录数

 


        /// </summary>
        /// <param name="SQLString">SQL语句</param>
        /// <returns>影响的记录数</returns>
        public static int ExecuteSql(string SQLString, params SqlParameter[] cmdParms)
        {
            using (SqlConnection connection = new SqlConnection(connectionString))
            {
                using (SqlCommand cmd = new SqlCommand())
                {
                    try
                    {
                        PrepareCommand(cmd, connection, null, SQLString, cmdParms);
                        int rows = cmd.ExecuteNonQuery();
                        cmd.Parameters.Clear();
                        return rows;
                    }
                    catch (System.Data.SqlClient.SqlException E)
                    {
                        throw new Exception(E.Message);
                    }
                }
            }
        }


        /**/
        /// <summary>
        /// 执行多条SQL语句，实现数据库事务。

 


     /// </summary>
        /// <param name="SQLStringList">SQL语句的哈希表（key为sql语句，value是该语句的SqlParameter[]）</param>
        public static void ExecuteSqlTran(Hashtable SQLStringList)
        {
            using (SqlConnection conn = new SqlConnection(connectionString))
            {
                conn.Open();
                using (SqlTransaction trans = conn.BeginTransaction())
                {
                    SqlCommand cmd = new SqlCommand();
                    try
                    {
                        //循环
                        foreach (DictionaryEntry myDE in SQLStringList)
                        {
                            string cmdText = myDE.Key.ToString();
                            SqlParameter[] cmdParms = (SqlParameter[])myDE.Value;
                            PrepareCommand(cmd, conn, trans, cmdText, cmdParms);
                            int val = cmd.ExecuteNonQuery();
                            cmd.Parameters.Clear();

                            trans.Commit();
                        }
                    }
                    catch
                    {
                        trans.Rollback();
                        throw;
                    }
                }
            }
        }


        /**/
        /// <summary>
        /// 执行一条计算查询结果语句，返回查询结果（object）。

 

 

        /// </summary>
        /// <param name="SQLString">计算查询结果语句</param>
        /// <returns>查询结果（object）</returns>
        public static object GetSingle(string SQLString, params SqlParameter[] cmdParms)
        {
            using (SqlConnection connection = new SqlConnection(connectionString))
            {
                using (SqlCommand cmd = new SqlCommand())
                {
                    try
                    {
                        PrepareCommand(cmd, connection, null, SQLString, cmdParms);
                        object obj = cmd.ExecuteScalar();
                        cmd.Parameters.Clear();
                        if ((Object.Equals(obj, null)) || (Object.Equals(obj, System.DBNull.Value)))
                        {
                            return null;
                        }
                        else
                        {
                            return obj;
                        }
                    }
                    catch (System.Data.SqlClient.SqlException e)
                    {
                        throw new Exception(e.Message);
                    }
                }
            }
        }


        /**/
        /// <summary>
        /// 执行查询语句，返回SqlDataReader
        /// </summary>
        /// <param name="strSQL">查询语句</param>
        /// <returns>SqlDataReader</returns>
        public static SqlDataReader ExecuteReader(string SQLString, params SqlParameter[] cmdParms)
        {
            SqlConnection connection = new SqlConnection(connectionString);
            SqlCommand cmd = new SqlCommand();
            try
            {
                PrepareCommand(cmd, connection, null, SQLString, cmdParms);
                SqlDataReader myReader = cmd.ExecuteReader();
                cmd.Parameters.Clear();
                return myReader;
            }
            catch (System.Data.SqlClient.SqlException e)
            {
                throw new Exception(e.Message);
            }

        }

        /**/
        /// <summary>
        /// 执行查询语句，返回DataSet
        /// </summary>
        /// <param name="SQLString">查询语句</param>
        /// <returns>DataSet</returns>
        public static DataSet QueryParas(string SQLString, params SqlParameter[] cmdParms)
        {
            using (SqlConnection connection = new SqlConnection(connectionString))
            {
                SqlCommand cmd = new SqlCommand();
                PrepareCommand(cmd, connection, null, SQLString, cmdParms);
                using (SqlDataAdapter da = new SqlDataAdapter(cmd))
                {
                    DataSet ds = new DataSet();
                    try
                    {
                        da.Fill(ds, "ds");
                        cmd.Parameters.Clear();
                    }
                    catch (System.Data.SqlClient.SqlException ex)
                    {
                        throw new Exception(ex.Message);
                    }
                    return ds;
                }
            }
        }
   


        private static void PrepareCommand(SqlCommand cmd, SqlConnection conn, SqlTransaction trans, 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 = CommandType.Text;//cmdType;
            if (cmdParms != null)
            {
                foreach (SqlParameter parm in cmdParms)
                    cmd.Parameters.Add(parm);
            }
        }

        #endregion

        #region 存储过程操作

        /**/
        /// <summary>
        /// 执行存储过程
        /// </summary>
        /// <param name="storedProcName">存储过程名</param>
        /// <param name="parameters">存储过程参数</param>
        /// <returns>SqlDataReader</returns>
        public static SqlDataReader RunProcedure(string storedProcName, IDataParameter[] parameters)
        {
            SqlConnection connection = new SqlConnection(connectionString);
            SqlDataReader returnReader;
            connection.Open();
            SqlCommand command = BuildQueryCommand(connection, storedProcName, parameters);
            command.CommandType = CommandType.StoredProcedure;
            returnReader = command.ExecuteReader();
            return returnReader;
        }


        /**/
        /// <summary>
        /// 执行存储过程
        /// </summary>
        /// <param name="storedProcName">存储过程名</param>
        /// <param name="parameters">存储过程参数</param>
        /// <param name="tableName">DataSet结果中的表名</param>
        /// <returns>DataSet</returns>
        public static DataSet RunProcedureParas(string storedProcName, IDataParameter[] parameters, string tableName)
        {
            using (SqlConnection connection = new SqlConnection(connectionString))
            {
                DataSet dataSet = new DataSet();
                connection.Open();
                SqlDataAdapter sqlDA = new SqlDataAdapter();
                sqlDA.SelectCommand = BuildQueryCommand(connection, storedProcName, parameters);
                sqlDA.Fill(dataSet, tableName);
                connection.Close();
                return dataSet;
            }
        }

        /**/
        /// <summary>
        /// 构建 SqlCommand 对象(用来返回一个结果集，而不是一个整数值)
        /// </summary>
        /// <param name="connection">数据库连接</param>
        /// <param name="storedProcName">存储过程名</param>
        /// <param name="parameters">存储过程参数</param>
        /// <returns>SqlCommand</returns>
        private static SqlCommand BuildQueryCommand(SqlConnection connection, string storedProcName, IDataParameter[] parameters)
        {
            SqlCommand command = new SqlCommand(storedProcName, connection);
            command.CommandType = CommandType.StoredProcedure;
            foreach (SqlParameter parameter in parameters)
            {
                command.Parameters.Add(parameter);
            }
            return command;
        }

        /**/
        /// <summary>
        /// 执行存储过程，返回影响的行数 
        /// </summary>
        /// <param name="storedProcName">存储过程名</param>
        /// <param name="parameters">存储过程参数</param>
        /// <param name="rowsAffected">影响的行数</param>
        /// <returns></returns>
        public static int RunProcedure(string storedProcName, IDataParameter[] parameters, out int rowsAffected)
        {
            using (SqlConnection connection = new SqlConnection(connectionString))
            {
                int result;
                connection.Open();
                SqlCommand command = BuildIntCommand(connection, storedProcName, parameters);
                rowsAffected = command.ExecuteNonQuery();
                result = (int)command.Parameters["ReturnValue"].Value;
                //Connection.Close();
                return result;
            }
        }

        /**/
        /// <summary>
        /// 创建 SqlCommand 对象实例(用来返回一个整数值)
        /// </summary>
        /// <param name="storedProcName">存储过程名</param>
        /// <param name="parameters">存储过程参数</param>
        /// <returns>SqlCommand 对象实例</returns>
        private static SqlCommand BuildIntCommand(SqlConnection connection, string storedProcName, IDataParameter[] parameters)
        {
            SqlCommand command = BuildQueryCommand(connection, storedProcName, parameters);
            command.Parameters.Add(new SqlParameter("ReturnValue",
             SqlDbType.Int, 4, ParameterDirection.ReturnValue,
             false, 0, 0, string.Empty, DataRowVersion.Default, null));
            return command;
        }
        #endregion

    }
}

lfgjtt
关注
Text2SQL推理类大模型本地部署的解决方案
herosunly的博客
03-27 14万+
本文主要介绍了Text2SQL推理类大模型本地部署的解决方案，希望对使用大语言模型的同学们有所帮助。 文章目录 1. 前言 2. 配置环境 2.1 安装虚拟环境 2.2 安装依赖库 2.3 下载模型 3. 实战代码
Android通过webservice连接Sqlserver实例
12-02
2. 数据库连接：在服务器端，配置SQLServer数据库连接字符串，确保服务器允许外部访问，并使用ADO.NET或其他数据库访问技术建立数据库连接。 步骤二：Android客户端准备 1. 添加依赖：在Android项目中，添加必要的...
非常实用的SqlHelper类
12-10
虽然是个辅助类，但是支持事务管理（仅单事务管理）。您可以通过继承或填充泛型参数直接操作其他类型的数据库，如Oracle、MySql等。 本SqlHelper类（在ZDevTools.Data命名空间中）最与众不同的地方在于兼顾了易用性与灵活性：她通过委托的方式将你要执行的操作传入SqlHelper类中，所有的连接操作自动维护，却能将DBDataReader、DBCommand这样功能强大的原始类型保留给调用者。 这里贴出一些方法签名： public void Execute(string sql, CommandType commandType, Action job, params TParameter[] parameters) public int Execute(string sql, CommandType commandType, params TParameter[] parameters) public void Execute(Action job) public T GetScalar(string sql, CommandType commandType, params TParameter[] parameters) public DataSet GetDataSet(string sql, CommandType commandType, params TParameter[] parameters) public void UpdateDataSet(string sql, DataSet dataSet) public DataTable GetDataTable(string sql, CommandType commandType, params TParameter[] parameters) public void UpdateDataTable(string sql, DataTable dataTable) public TParameter CreateParameter(string name, DbType dbType, object value) 在ZDevTools.UI.WinForm命名空间下还有一个非常好用的自动完成控件，欢迎使用。
MsSqlHelper_MsSqlHelper.cs_
10-02
asp.net
SQLhelp帮助类及使用方法
07-06
连接SQLserver的帮助类，多种方法，非常详细，附使用方法
数据库连接层代码
weixin_30341745的博客
10-17 119
using System;using System.Data;using System.Data.SqlClient;using System.Collections;using System.Collections.Specialized;using System.Configuration;using System.Web;using System.Web.Security;using Sys...
SQLHelper常用代码
AronZhang的博客
08-14 380
public class SqlHelper { private static readonly string connStr = ConfigurationManager.ConnectionStrings["FanQieDian"].ConnectionString;//在web.config里配置ConnectionStrings /// <summary> /// 获取表数据 /// </summary>
java连接SqlServer完整代码，工具类，jdbc
01-21
java连接SqlServer完整代码，工具类，jdbc JDBC工具类的构建 1.资源释放 见https://mp.youkuaiyun.com/postedit/86577443 2.驱动防二次注册 ``` Class.forName("com.microsoft.sqlserver.jdbc.SQLServerDriver"); //...
SQL连接java
10-27
用于SQL2005连接Java编程应用的专门代码，但是user和password要根据用户更改。
精选资源
C#SqlServer数据库链接帮助类
03-02
C#SqlServer数据库链接帮助类
微软SQLHelper.cs类 中文版
07-30
微软SQLHelper.cs类 中文版 sql数据库工具类
SqlHelper.cs
03-03
SqlHelper.cs
Mysql Helper 最好用的 MysqlHelper.cs （MySql.Data.dll）
08-15
最好用的 MysqlHelper.cs，Mysql Helper 本人多次改进和调整，处理了MySql.Data.dll 中的多个bug导致的程序异常，执行快速，使用方便。【来自金花工具】
MySQLHelp.cs+MySql.Data.dll
09-23
MySQL数据库连接驱动MySql.Data.dll 数据库操作小助理 MySQLHelp.cs 执行带参数的SQL语句 执行简单SQL语句
C#操作各种数据库底层源码 连接数据库代码
08-06
C#操作数据库 底层源码 项目框架建设 Access MySQL SQLServer 很全，代码写的很完美，完全开源。适合前期框架搭建、操作数据库底层代码
整理出一个比较实用的SqlHelper类 满足大多数情况的使用
这里将承载一段最初的记忆
03-17 515
整理出一个比较实用的SqlHelper类 满足大多数情况的使用 　　 /// &lt;summary&gt; /// SqlHelper类 by zy 2017-8-17 /// &lt;/summary&gt; public sealed class SqlHelper { //如果...
DBHelper
难求 专栏
05-04 663
public abstract class DbHelperSQL { //数据库连接字符串(web.config来配置) //  protected static string connectionString = ConfigurationSettings.AppSettings["ConnectionString"]; public DbHelperSQL() { } #
操作数据库的类DbHelper.cs
yunduan的专栏
03-20 4175
using System;using System.Data;using System.Data.Common;using System.Configuration;namespace Utility{    public class DbHelper    {        private static string dbProviderName = ConfigurationManager.A
微软官方的SQLHelper类(含完整中文注释)
q1063823095的博客
06-26 5757
[csharp] view plain copy print?using System;  using System.Data;  using System.Xml;  using System.Data.SqlClient;  using System.Collections;  namespace myhelper  {      /// <summary>      /// SqlServer
评论
成就一亿技术人!
拼手气红包6.0元
还能输入1000个字符
 
红包 添加红包
表情包 插入表情
表情包 代码片
 条评论被折叠 查看
添加红包

请填写红包祝福语或标题

个

红包个数最小为10个

元

红包金额最低5元

当前余额3.43元 前往充值 >
需支付：10.00元
成就一亿技术人!
领取后你会自动成为博主和红包主的粉丝 规则
hope_wisdom
发出的红包
实付元
使用余额支付
点击重新获取
扫码支付
钱包余额 0

抵扣说明：

1.余额是钱包充值的虚拟货币，按照1:1的比例进行支付金额的抵扣。
2.余额无法直接购买下载，可以购买VIP、付费专栏及课程。

余额充值