C#訪問MySQL資料庫幫助類
阿新 • • 發佈:2019-01-26
轉載地址:http://www.cnblogs.com/JiYF/p/6572614.html
MySQL資料庫訪問幫助類
1.專案新增引用官方MySQL動態庫MySql.Data.dll
專案新增引用
2.web.config配置資料庫連線字串
<?xml version="1.0"?> <configuration> <appSettings> <!-- 連線字串是否加密 --> <add key="ConStringEncrypt" value="false"/> <!-- 資料庫連線字串,(如果採用加密方式,上面一項要設定為true;加密工具,可在官方下載, 如果使用明文這樣server=127.0.0.1;database=.....,上面則設定為false。 --> <add key="ConnectionString" value="server=127.0.0.1;database=BenXHCMS;uid=sa;pwd=jyf"/> </appSettings> </configuration>
3.資料庫字串讀取類(多一個加密演算法,可以自己新增)
public class PubConstant { /// <summary> /// 獲取連線字串 /// </summary> public static string ConnectionString { get { string _connectionString = ConfigurationManager.AppSettings["ConnectionString"]; string ConStringEncrypt = ConfigurationManager.AppSettings["ConStringEncrypt"]; if (ConStringEncrypt == "true") { _connectionString = DESEncrypt.Decrypt(_connectionString); } return _connectionString; } } /// <summary> /// 得到web.config裡配置項的資料庫連線字串。 /// </summary> /// <param name="configName"></param> /// <returns></returns> public static string GetConnectionString(string configName) { string connectionString = ConfigurationManager.AppSettings[configName]; string ConStringEncrypt = ConfigurationManager.AppSettings["ConStringEncrypt"]; if (ConStringEncrypt == "true") { connectionString = DESEncrypt.Decrypt(connectionString); } return connectionString; } }
4.MySQL資料庫訪問類--注意:對 MySql.Data.MySqlClient引用
using System; using System.Collections; using System.Collections.Specialized; using System.Data; using MySql.Data.MySqlClient; using System.Configuration; using System.Data.Common; using System.Collections.Generic; namespace Maticsoft.DBUtility { /// <summary> /// 資料訪問抽象基礎類 /// Copyright (C) Maticsoft /// </summary> public abstract class DbHelperMySQL { //資料庫連線字串(web.config來配置),可以動態更改connectionString支援多資料庫. public static string connectionString = PubConstant.ConnectionString; public DbHelperMySQL() { } #region 公用方法 /// <summary> /// 得到最大值 /// </summary> /// <param name="FieldName"></param> /// <param name="TableName"></param> /// <returns></returns> 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()); } } /// <summary> /// 是否存在 /// </summary> /// <param name="strSql"></param> /// <returns></returns> 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; } } /// <summary> /// 是否存在(基於MySqlParameter) /// </summary> /// <param name="strSql"></param> /// <param name="cmdParms"></param> /// <returns></returns> public static bool Exists(string strSql, params MySqlParameter[] 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 執行簡單SQL語句 /// <summary> /// 執行SQL語句,返回影響的記錄數 /// </summary> /// <param name="SQLString">SQL語句</param> /// <returns>影響的記錄數</returns> public static int ExecuteSql(string SQLString) { using (MySqlConnection connection = new MySqlConnection(connectionString)) { using (MySqlCommand cmd = new MySqlCommand(SQLString, connection)) { try { connection.Open(); int rows = cmd.ExecuteNonQuery(); return rows; } catch (MySql.Data.MySqlClient.MySqlException e) { connection.Close(); throw e; } } } } public static int ExecuteSqlByTime(string SQLString, int Times) { using (MySqlConnection connection = new MySqlConnection(connectionString)) { using (MySqlCommand cmd = new MySqlCommand(SQLString, connection)) { try { connection.Open(); cmd.CommandTimeout = Times; int rows = cmd.ExecuteNonQuery(); return rows; } catch (MySql.Data.MySqlClient.MySqlException e) { connection.Close(); throw e; } } } } /// <summary> /// 執行MySql和Oracle滴混合事務 /// </summary> /// <param name="list">SQL命令列列表</param> /// <param name="oracleCmdSqlList">Oracle命令列列表</param> /// <returns>執行結果 0-由於SQL造成事務失敗 -1 由於Oracle造成事務失敗 1-整體事務執行成功</returns> public static int ExecuteSqlTran(List<CommandInfo> list, List<CommandInfo> oracleCmdSqlList) { using (MySqlConnection conn = new MySqlConnection(connectionString)) { conn.Open(); MySqlCommand cmd = new MySqlCommand(); cmd.Connection = conn; MySqlTransaction tx = conn.BeginTransaction(); cmd.Transaction = tx; try { foreach (CommandInfo myDE in list) { string cmdText = myDE.CommandText; MySqlParameter[] cmdParms = (MySqlParameter[])myDE.Parameters; PrepareCommand(cmd, conn, tx, cmdText, cmdParms); if (myDE.EffentNextType == EffentNextType.SolicitationEvent) { if (myDE.CommandText.ToLower().IndexOf("count(") == -1) { tx.Rollback(); throw new Exception("違背要求"+myDE.CommandText+"必須符合select count(..的格式"); //return 0; } object obj = cmd.ExecuteScalar(); bool isHave = false; if (obj == null && obj == DBNull.Value) { isHave = false; } isHave = Convert.ToInt32(obj) > 0; if (isHave) { //引發事件 myDE.OnSolicitationEvent(); } } if (myDE.EffentNextType == EffentNextType.WhenHaveContine || myDE.EffentNextType == EffentNextType.WhenNoHaveContine) { if (myDE.CommandText.ToLower().IndexOf("count(") == -1) { tx.Rollback(); throw new Exception("SQL:違背要求" + myDE.CommandText + "必須符合select count(..的格式"); //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) { tx.Rollback(); throw new Exception("SQL:違背要求" + myDE.CommandText + "返回值必須大於0"); //return 0; } if (myDE.EffentNextType == EffentNextType.WhenNoHaveContine && isHave) { tx.Rollback(); throw new Exception("SQL:違背要求" + myDE.CommandText + "返回值必須等於0"); //return 0; } continue; } int val = cmd.ExecuteNonQuery(); if (myDE.EffentNextType == EffentNextType.ExcuteEffectRows && val == 0) { tx.Rollback(); throw new Exception("SQL:違背要求" + myDE.CommandText + "必須有影響行"); //return 0; } cmd.Parameters.Clear(); } string oraConnectionString = PubConstant.GetConnectionString("ConnectionStringPPC"); bool res = OracleHelper.ExecuteSqlTran(oraConnectionString, oracleCmdSqlList); if (!res) { tx.Rollback(); throw new Exception("執行失敗"); // return -1; } tx.Commit(); return 1; } catch (MySql.Data.MySqlClient.MySqlException e) { tx.Rollback(); throw e; } catch (Exception e) { tx.Rollback(); throw e; } } } /// <summary> /// 執行多條SQL語句,實現資料庫事務。 /// </summary> /// <param name="SQLStringList">多條SQL語句</param> public static int ExecuteSqlTran(List<String> SQLStringList) { using (MySqlConnection conn = new MySqlConnection(connectionString)) { conn.Open(); MySqlCommand cmd = new MySqlCommand(); cmd.Connection = conn; MySqlTransaction 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; } } } /// <summary> /// 執行帶一個儲存過程引數的的SQL語句。 /// </summary> /// <param name="SQLString">SQL語句</param> /// <param name="content">引數內容,比如一個欄位是格式複雜的文章,有特殊符號,可以通過這個方式新增</param> /// <returns>影響的記錄數</returns> public static int ExecuteSql(string SQLString, string content) { using (MySqlConnection connection = new MySqlConnection(connectionString)) { MySqlCommand cmd = new MySqlCommand(SQLString, connection); MySql.Data.MySqlClient.MySqlParameter myParameter = new MySql.Data.MySqlClient.MySqlParameter("@content", SqlDbType.NText); myParameter.Value = content; cmd.Parameters.Add(myParameter); try { connection.Open(); int rows = cmd.ExecuteNonQuery(); return rows; } catch (MySql.Data.MySqlClient.MySqlException e) { throw e; } finally { cmd.Dispose(); connection.Close(); } } } /// <summary> /// 執行帶一個儲存過程引數的的SQL語句。 /// </summary> /// <param name="SQLString">SQL語句</param> /// <param name="content">引數內容,比如一個欄位是格式複雜的文章,有特殊符號,可以通過這個方式新增</param> /// <returns>影響的記錄數</returns> public static object ExecuteSqlGet(string SQLString, string content) { using (MySqlConnection connection = new MySqlConnection(connectionString)) { MySqlCommand cmd = new MySqlCommand(SQLString, connection); MySql.Data.MySqlClient.MySqlParameter myParameter = new MySql.Data.MySqlClient.MySqlParameter("@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 (MySql.Data.MySqlClient.MySqlException e) { throw e; } finally { cmd.Dispose(); connection.Close(); } } } /// <summary> /// 向資料庫裡插入影象格式的欄位(和上面情況類似的另一種例項) /// </summary> /// <param name="strSQL">SQL語句</param> /// <param name="fs">影象位元組,資料庫的欄位型別為image的情況</param> /// <returns>影響的記錄數</returns> public static int ExecuteSqlInsertImg(string strSQL, byte[] fs) { using (MySqlConnection connection = new MySqlConnection(connectionString)) { MySqlCommand cmd = new MySqlCommand(strSQL, connection); MySql.Data.MySqlClient.MySqlParameter myParameter = new MySql.Data.MySqlClient.MySqlParameter("@fs", SqlDbType.Image); myParameter.Value = fs; cmd.Parameters.Add(myParameter); try { connection.Open(); int rows = cmd.ExecuteNonQuery(); return rows; } catch (MySql.Data.MySqlClient.MySqlException e) { throw e; } finally { cmd.Dispose(); connection.Close(); } } } /// <summary> /// 執行一條計算查詢結果語句,返回查詢結果(object)。 /// </summary> /// <param name="SQLString">計算查詢結果語句</param> /// <returns>查詢結果(object)</returns> public static object GetSingle(string SQLString) { using (MySqlConnection connection = new MySqlConnection(connectionString)) { using (MySqlCommand cmd = new MySqlCommand(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 (MySql.Data.MySqlClient.MySqlException e) { connection.Close(); throw e; } } } } public static object GetSingle(string SQLString, int Times) { using (MySqlConnection connection = new MySqlConnection(connectionString)) { using (MySqlCommand cmd = new MySqlCommand(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 (MySql.Data.MySqlClient.MySqlException e) { connection.Close(); throw e; } } } } /// <summary> /// 執行查詢語句,返回MySqlDataReader ( 注意:呼叫該方法後,一定要對MySqlDataReader進行Close ) /// </summary> /// <param name="strSQL">查詢語句</param> /// <returns>MySqlDataReader</returns> public static MySqlDataReader ExecuteReader(string strSQL) { MySqlConnection connection = new MySqlConnection(connectionString); MySqlCommand cmd = new MySqlCommand(strSQL, connection); try { connection.Open(); MySqlDataReader myReader = cmd.ExecuteReader(CommandBehavior.CloseConnection); return myReader; } catch (MySql.Data.MySqlClient.MySqlException e) { throw e; } } /// <summary> /// 執行查詢語句,返回DataSet /// </summary> /// <param name="SQLString">查詢語句</param> /// <returns>DataSet</returns> public static DataSet Query(string SQLString) { using (MySqlConnection connection = new MySqlConnection(connectionString)) { DataSet ds = new DataSet(); try { connection.Open(); MySqlDataAdapter command = new MySqlDataAdapter(SQLString, connection); command.Fill(ds, "ds"); } catch (MySql.Data.MySqlClient.MySqlException ex) { throw new Exception(ex.Message); } return ds; } } public static DataSet Query(string SQLString, int Times) { using (MySqlConnection connection = new MySqlConnection(connectionString)) { DataSet ds = new DataSet(); try { connection.Open(); MySqlDataAdapter command = new MySqlDataAdapter(SQLString, connection); command.SelectCommand.CommandTimeout = Times; command.Fill(ds, "ds"); } catch (MySql.Data.MySqlClient.MySqlException ex) { throw new Exception(ex.Message); } return ds; } } #endregion #region 執行帶引數的SQL語句 /// <summary> /// 執行SQL語句,返回影響的記錄數 /// </summary> /// <param name="SQLString">SQL語句</param> /// <returns>影響的記錄數</returns> public static int ExecuteSql(string SQLString, params MySqlParameter[] cmdParms) { using (MySqlConnection connection = new MySqlConnection(connectionString)) { using (MySqlCommand cmd = new MySqlCommand()) { try { PrepareCommand(cmd, connection, null, SQLString, cmdParms); int rows = cmd.ExecuteNonQuery(); cmd.Parameters.Clear(); return rows; } catch (MySql.Data.MySqlClient.MySqlException e) { throw e; } } } } /// <summary> /// 執行多條SQL語句,實現資料庫事務。 /// </summary> /// <param name="SQLStringList">SQL語句的雜湊表(key為sql語句,value是該語句的MySqlParameter[])</param> public static void ExecuteSqlTran(Hashtable SQLStringList) { using (MySqlConnection conn = new MySqlConnection(connectionString)) { conn.Open(); using (MySqlTransaction trans = conn.BeginTransaction()) { MySqlCommand cmd = new MySqlCommand(); try { //迴圈 foreach (DictionaryEntry myDE in SQLStringList) { string cmdText = myDE.Key.ToString(); MySqlParameter[] cmdParms = (MySqlParameter[])myDE.Value; PrepareCommand(cmd, conn, trans, cmdText, cmdParms); int val = cmd.ExecuteNonQuery(); cmd.Parameters.Clear(); } trans.Commit(); } catch { trans.Rollback(); throw; } } } } /// <summary> /// 執行多條SQL語句,實現資料庫事務。 /// </summary> /// <param name="SQLStringList">SQL語句的雜湊表(key為sql語句,value是該語句的MySqlParameter[])</param> public static int ExecuteSqlTran(System.Collections.Generic.List<CommandInfo> cmdList) { using (MySqlConnection conn = new MySqlConnection(connectionString)) { conn.Open(); using (MySqlTransaction trans = conn.BeginTransaction()) { MySqlCommand cmd = new MySqlCommand(); try { int count = 0; //迴圈 foreach (CommandInfo myDE in cmdList) { string cmdText = myDE.CommandText; MySqlParameter[] cmdParms = (MySqlParameter[])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; } } } } /// <summary> /// 執行多條SQL語句,實現資料庫事務。 /// </summary> /// <param name="SQLStringList">SQL語句的雜湊表(key為sql語句,value是該語句的MySqlParameter[])</param> public static void ExecuteSqlTranWithIndentity(System.Collections.Generic.List<CommandInfo> SQLStringList) { using (MySqlConnection conn = new MySqlConnection(connectionString)) { conn.Open(); using (MySqlTransaction trans = conn.BeginTransaction()) { MySqlCommand cmd = new MySqlCommand(); try { int indentity = 0; //迴圈 foreach (CommandInfo myDE in SQLStringList) { string cmdText = myDE.CommandText; MySqlParameter[] cmdParms = (MySqlParameter[])myDE.Parameters; foreach (MySqlParameter q in cmdParms) { if (q.Direction == ParameterDirection.InputOutput) { q.Value = indentity; } } PrepareCommand(cmd, conn, trans, cmdText, cmdParms); int val = cmd.ExecuteNonQuery(); foreach (MySqlParameter q in cmdParms) { if (q.Direction == ParameterDirection.Output) { indentity = Convert.ToInt32(q.Value); } } cmd.Parameters.Clear(); } trans.Commit(); } catch { trans.Rollback(); throw; } } } } /// <summary> /// 執行多條SQL語句,實現資料庫事務。 /// </summary> /// <param name="SQLStringList">SQL語句的雜湊表(key為sql語句,value是該語句的MySqlParameter[])</param> public static void ExecuteSqlTranWithIndentity(Hashtable SQLStringList) { using (MySqlConnection conn = new MySqlConnection(connectionString)) { conn.Open(); using (MySqlTransaction trans = conn.BeginTransaction()) { MySqlCommand cmd = new MySqlCommand(); try { int indentity = 0; //迴圈 foreach (DictionaryEntry myDE in SQLStringList) { string cmdText = myDE.Key.ToString(); MySqlParameter[] cmdParms = (MySqlParameter[])myDE.Value; foreach (MySqlParameter q in cmdParms) { if (q.Direction == ParameterDirection.InputOutput) { q.Value = indentity; } } PrepareCommand(cmd, conn, trans, cmdText, cmdParms); int val = cmd.ExecuteNonQuery(); foreach (MySqlParameter q in cmdParms) { if (q.Direction == ParameterDirection.Output) { indentity = Convert.ToInt32(q.Value); } } cmd.Parameters.Clear(); } trans.Commit(); } catch { trans.Rollback(); throw; } } } } /// <summary> /// 執行一條計算查詢結果語句,返回查詢結果(object)。 /// </summary> /// <param name="SQLString">計算查詢結果語句</param> /// <returns>查詢結果(object)</returns> public static object GetSingle(string SQLString, params MySqlParameter[] cmdParms) { using (MySqlConnection connection = new MySqlConnection(connectionString)) { using (MySqlCommand cmd = new MySqlCommand()) { 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 (MySql.Data.MySqlClient.MySqlException e) { throw e; } } } } /// <summary> /// 執行查詢語句,返回MySqlDataReader ( 注意:呼叫該方法後,一定要對MySqlDataReader進行Close ) /// </summary> /// <param name="strSQL">查詢語句</param> /// <returns>MySqlDataReader</returns> public static MySqlDataReader ExecuteReader(string SQLString, params MySqlParameter[] cmdParms) { MySqlConnection connection = new MySqlConnection(connectionString); MySqlCommand cmd = new MySqlCommand(); try { PrepareCommand(cmd, connection, null, SQLString, cmdParms); MySqlDataReader myReader = cmd.ExecuteReader(CommandBehavior.CloseConnection); cmd.Parameters.Clear(); return myReader; } catch (MySql.Data.MySqlClient.MySqlException e) { throw e; } // finally // { // cmd.Dispose(); // connection.Close(); // } } /// <summary> /// 執行查詢語句,返回DataSet /// </summary> /// <param name="SQLString">查詢語句</param> /// <returns>DataSet</returns> public static DataSet Query(string SQLString, params MySqlParameter[] cmdParms) { using (MySqlConnection connection = new MySqlConnection(connectionString)) { MySqlCommand cmd = new MySqlCommand(); PrepareCommand(cmd, connection, null, SQLString, cmdParms); using (MySqlDataAdapter da = new MySqlDataAdapter(cmd)) { DataSet ds = new DataSet(); try { da.Fill(ds, "ds"); cmd.Parameters.Clear(); } catch (MySql.Data.MySqlClient.MySqlException ex) { throw new Exception(ex.Message); } return ds; } } } private static void PrepareCommand(MySqlCommand cmd, MySqlConnection conn, MySqlTransaction trans, string cmdText, MySqlParameter[] 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 (MySqlParameter parameter in cmdParms) { if ((parameter.Direction == ParameterDirection.InputOutput || parameter.Direction == ParameterDirection.Input) && (parameter.Value == null)) { parameter.Value = DBNull.Value; } cmd.Parameters.Add(parameter); } } } #endregion } }