如何使dbhelper类中的内容修改后使引用dbhelper.dll也更改-CSDN社区

数据库操作类（支持OleDb、MySQL、Oracle、SQL、SQLite、）操作：获取连接字符串得到web.config里配置项的数据库连接字符串。数据库连接字符串(web.config来配置)，可以动态更改connectionString支持多数据库. 得到最大值是否存在是否存在（基于MySqlParameter）执行SQL语句，返回影响的记录数执行MySql和Oracle滴混合事务执行多条SQL语句，实现数据库事务。执行带一个存储过程参数的的SQL语句。向数据库里插入图像格式的字段执行一条计算查询结果语句，返回查询结果执行查询语句，返回MySqlDataReader 执行查询语句，返回DataSet 执行SQL语句，返回影响的记录数执行多条SQL语句，实现数据库事务。执行带一个存储过程参数的的SQL语句。 DES加密/解密类

一款特别好用的.net数据库链接通用类。 using System; using System.Collections; using System.Collections.Specialized; using System.Data; using System.Data.SqlClient; using System.Configuration; using System.Data.Common; using System.Collections.Generic; namespace CMS.DBUtility { ///

public abstract class DbHelperSQL { //数据库连接字符串(web.config来配置)，可以动态更改connectionString支持多数据库. public static string connectionString = PubConstant.ConnectionString; public DbHelperSQL() { } #region 公用方法 ///

/// 判断是否存在某表的某个字段 ///

/// 表名称 /// 列名称 /// 是否存在 public static bool ColumnExists(string tableName, string columnName) { string sql = "select count(1) from syscolumns where [id]=object_id('" + tableName + "') and [name]='" + columnName + "'"; object res = GetSingle(sql); if (res == null) { return false; } return Convert.ToInt32(res) > 0; } 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) { object obj = GetSingle(strSql); 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; } } ///

/// 表是否存在 ///

/// /// public static bool TabExists(string TableName) { string strsql = "select count(*) from sysobjects where id = object_id(N'[" + TableName + "]') and OBJECTPROPERTY(id, N'IsUserTable') = 1"; //string strsql = "SELECT count(*) FROM sys.objects WHERE object_id = OBJECT_ID(N'[dbo].[" + TableName + "]') AND type in (N'U')"; object obj = GetSingle(strsql); 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; } } 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 ///

/// 执行SQL语句，返回影响的记录数 ///

/// SQL语句 /// 影响的记录数 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 e; } } } } public static int ExecuteSqlByTime(string SQLString, int Times) { using (SqlConnection connection = new SqlConnection(connectionString)) { using (SqlCommand cmd = new SqlCommand(SQLString, connection)) { try { connection.Open(); cmd.CommandTimeout = Times; int rows = cmd.ExecuteNonQuery(); return rows; } catch (System.Data.SqlClient.SqlException e) { connection.Close(); throw e; } } } } ///

/// 执行Sql和Oracle滴混合事务 ///

/// 执行多条SQL语句，实现数据库事务。 ///

/// 多条SQL语句 public static int ExecuteSqlTran(List SQLStringList) { using (SqlConnection conn = new SqlConnection(connectionString)) { conn.Open(); SqlCommand cmd = new SqlCommand(); cmd.Connection = conn; SqlTransaction tx = conn.BeginTransaction(); cmd.Transaction = tx; try { int count = 0; for (int n = 0; n < SQLStringList.Count; n++) { string strsql = SQLStringList[n]; if (strsql.Trim().Length > 1) { cmd.CommandText = strsql; count += cmd.ExecuteNonQuery(); } } tx.Commit(); return count; } catch { tx.Rollback(); return 0; } } } ///

/// 执行带一个存储过程参数的的SQL语句。 ///

/// SQL语句 /// 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 /// 影响的记录数 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 e; } finally { cmd.Dispose(); connection.Close(); } } } ///

/// 执行带一个存储过程参数的的SQL语句。 ///

/// SQL语句 /// 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 /// 影响的记录数 public static object ExecuteSqlGet(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(); 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) { throw e; } finally { cmd.Dispose(); connection.Close(); } } } ///

/// 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) ///

/// SQL语句 /// 图像字节,数据库的字段类型为image的情况 /// 影响的记录数 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 e; } finally { cmd.Dispose(); connection.Close(); } } } ///

/// 执行一条计算查询结果语句，返回查询结果（object）。 ///

/// 计算查询结果语句 /// 查询结果（object） public static object GetSingle(string SQLString) { 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 e; } } } } public static object GetSingle(string SQLString, int Times) { using (SqlConnection connection = new SqlConnection(connectionString)) { using (SqlCommand cmd = new SqlCommand(SQLString, connection)) { try { connection.Open(); cmd.CommandTimeout = Times; 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 e; } } } } ///

/// 执行查询语句，返回SqlDataReader ( 注意：调用该方法后，一定要对SqlDataReader进行Close ) ///

/// 查询语句 /// SqlDataReader public static SqlDataReader ExecuteReader(string strSQL) { SqlConnection connection = new SqlConnection(connectionString); SqlCommand cmd = new SqlCommand(strSQL, connection); try { connection.Open(); SqlDataReader myReader = cmd.ExecuteReader(CommandBehavior.CloseConnection); return myReader; } catch (System.Data.SqlClient.SqlException e) { throw e; } } ///

/// 执行查询语句，返回DataSet ///

/// 查询语句 /// DataSet 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; } } public static DataSet Query(string SQLString, int Times) { using (SqlConnection connection = new SqlConnection(connectionString)) { DataSet ds = new DataSet(); try { connection.Open(); SqlDataAdapter command = new SqlDataAdapter(SQLString, connection); command.SelectCommand.CommandTimeout = Times; 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 ///

/// 执行SQL语句，返回影响的记录数 ///

/// SQL语句 /// 影响的记录数 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 e; } } } } ///

/// 执行多条SQL语句，实现数据库事务。 ///

/// SQL语句的哈希表（key为sql语句，value是该语句的SqlParameter[]） 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; } } } } ///

/// 执行多条SQL语句，实现数据库事务。 ///

/// SQL语句的哈希表（key为sql语句，value是该语句的SqlParameter[]） public static int ExecuteSqlTran(System.Collections.Generic.List cmdList) { using (SqlConnection conn = new SqlConnection(connectionString)) { conn.Open(); using (SqlTransaction trans = conn.BeginTransaction()) { SqlCommand cmd = new SqlCommand(); try { int count = 0; //循环 foreach (CommandInfo myDE in cmdList) { string cmdText = myDE.CommandText; SqlParameter[] cmdParms = (SqlParameter[])myDE.Parameters; PrepareCommand(cmd, conn, trans, cmdText, cmdParms); if (myDE.EffentNextType == EffentNextType.WhenHaveContine || myDE.EffentNextType == EffentNextType.WhenNoHaveContine) { if (myDE.CommandText.ToLower().IndexOf("count(") == -1) { trans.Rollback(); return 0; } object obj = cmd.ExecuteScalar(); bool isHave = false; if (obj == null && obj == DBNull.Value) { isHave = false; } isHave = Convert.ToInt32(obj) > 0; if (myDE.EffentNextType == EffentNextType.WhenHaveContine && !isHave) { trans.Rollback(); return 0; } if (myDE.EffentNextType == EffentNextType.WhenNoHaveContine && isHave) { trans.Rollback(); return 0; } continue; } int val = cmd.ExecuteNonQuery(); count += val; if (myDE.EffentNextType == EffentNextType.ExcuteEffectRows && val == 0) { trans.Rollback(); return 0; } cmd.Parameters.Clear(); } trans.Commit(); return count; } catch { trans.Rollback(); throw; } } } } ///

/// 执行多条SQL语句，实现数据库事务。 ///

/// SQL语句的哈希表（key为sql语句，value是该语句的SqlParameter[]） public static void ExecuteSqlTranWithIndentity(System.Collections.Generic.List SQLStringList) { using (SqlConnection conn = new SqlConnection(connectionString)) { conn.Open(); using (SqlTransaction trans = conn.BeginTransaction()) { SqlCommand cmd = new SqlCommand(); try { int indentity = 0; //循环 foreach (CommandInfo myDE in SQLStringList) { string cmdText = myDE.CommandText; SqlParameter[] cmdParms = (SqlParameter[])myDE.Parameters; foreach (SqlParameter q in cmdParms) { if (q.Direction == ParameterDirection.InputOutput) { q.Value = indentity; } } PrepareCommand(cmd, conn, trans, cmdText, cmdParms); int val = cmd.ExecuteNonQuery(); foreach (SqlParameter q in cmdParms) { if (q.Direction == ParameterDirection.Output) { indentity = Convert.ToInt32(q.Value); } } cmd.Parameters.Clear(); } trans.Commit(); } catch { trans.Rollback(); throw; } } } } ///

/// 执行多条SQL语句，实现数据库事务。 ///

/// SQL语句的哈希表（key为sql语句，value是该语句的SqlParameter[]） public static void ExecuteSqlTranWithIndentity(Hashtable SQLStringList) { using (SqlConnection conn = new SqlConnection(connectionString)) { conn.Open(); using (SqlTransaction trans = conn.BeginTransaction()) { SqlCommand cmd = new SqlCommand(); try { int indentity = 0; //循环 foreach (DictionaryEntry myDE in SQLStringList) { string cmdText = myDE.Key.ToString(); SqlParameter[] cmdParms = (SqlParameter[])myDE.Value; foreach (SqlParameter q in cmdParms) { if (q.Direction == ParameterDirection.InputOutput) { q.Value = indentity; } } PrepareCommand(cmd, conn, trans, cmdText, cmdParms); int val = cmd.ExecuteNonQuery(); foreach (SqlParameter q in cmdParms) { if (q.Direction == ParameterDirection.Output) { indentity = Convert.ToInt32(q.Value); } } cmd.Parameters.Clear(); } trans.Commit(); } catch { trans.Rollback(); throw; } } } } ///

/// 执行一条计算查询结果语句，返回查询结果（object）。 ///

/// 计算查询结果语句 /// 查询结果（object） 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 e; } } } } ///

/// 执行查询语句，返回SqlDataReader ( 注意：调用该方法后，一定要对SqlDataReader进行Close ) ///

/// 查询语句 /// SqlDataReader 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(CommandBehavior.CloseConnection); cmd.Parameters.Clear(); return myReader; } catch (System.Data.SqlClient.SqlException e) { throw e; } // finally // { // cmd.Dispose(); // connection.Close(); // } } ///

/// 执行查询语句，返回DataSet ///

/// 查询语句 /// DataSet public static DataSet Query(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 parameter in cmdParms) { if ((parameter.Direction == ParameterDirection.InputOutput || parameter.Direction == ParameterDirection.Input) && (parameter.Value == null)) { parameter.Value = DBNull.Value; } cmd.Parameters.Add(parameter); } } } #endregion #region 存储过程操作 ///

/// 执行存储过程，返回SqlDataReader ( 注意：调用该方法后，一定要对SqlDataReader进行Close ) ///

/// 存储过程名 /// 存储过程参数 /// SqlDataReader 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(CommandBehavior.CloseConnection); return returnReader; } ///

/// 执行存储过程 ///

/// 存储过程名 /// 存储过程参数 /// DataSet结果中的表名 /// DataSet public static DataSet RunProcedure(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; } } public static DataSet RunProcedure(string storedProcName, IDataParameter[] parameters, string tableName, int Times) { using (SqlConnection connection = new SqlConnection(connectionString)) { DataSet dataSet = new DataSet(); connection.Open(); SqlDataAdapter sqlDA = new SqlDataAdapter(); sqlDA.SelectCommand = BuildQueryCommand(connection, storedProcName, parameters); sqlDA.SelectCommand.CommandTimeout = Times; sqlDA.Fill(dataSet, tableName); connection.Close(); return dataSet; } } ///

/// 构建 SqlCommand 对象(用来返回一个结果集，而不是一个整数值) ///

/// 数据库连接 /// 存储过程名 /// 存储过程参数 /// SqlCommand 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) { if (parameter != null) { // 检查未分配值的输出参数,将其分配以DBNull.Value. if ((parameter.Direction == ParameterDirection.InputOutput || parameter.Direction == ParameterDirection.Input) && (parameter.Value == null)) { parameter.Value = DBNull.Value; } command.Parameters.Add(parameter); } } return command; } ///

/// 执行存储过程，返回影响的行数 ///

/// 存储过程名 /// 存储过程参数 /// 影响的行数 /// 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; } } ///

/// 创建 SqlCommand 对象实例(用来返回一个整数值) ///

/// 存储过程名 /// 存储过程参数 /// SqlCommand 对象实例 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 } }

网站建设中vs连接数据库的封装类，配置文件Web.Config需要自己写

在刚接触C#的时候由于公司使用的就是Oracle数据库，那么C#怎么连接Oracle数据库就成了首要去掌握的知识点了。在那时没有ODP.NET，但visual studio却对Oralce数据库的调用进行了集成，就是下图中的这个，尽管现在使用这个的时候visual studio提醒过时的，但在那时却是非常好用的。为什么现在visual studio中这个程序集依然能使用，有ODP.NET，...

介绍目前网络上的SqlHelper的各种改版版本很多，但大多数都是散乱而没有整体思路，一此只是静态方法，显的散乱的代码让程序无法很好的维护，有的繁琐的对象封装，使程序性能降低、维护复杂。最近发现国外网站的www.dbhlper.org发布了最新的SqlHelper版本，不仅仅代码精炼，而且体系清晰。用轻松的代码可支持强大的数据操作。我爱不释手，特写此文记下。使用步骤很简单： 1...