C# · 12月 26, 2021

C# Oracle数据库操作类实例详解

本文所述为C#实现的Oracle数据库操作类,可执行超多常用的Oracle数据库操作,包含了基础数据库连接、关闭连接、输出记录集、执行sql语句,返回带分页功能的dataset 、取表里字段的类型和长度等,同时还有哈稀表自动插入数据库等高级任务。需要特别指出的是:在执行sql语句,返回 DataReader之前一定要先用.read()打开,然后才能读到数据,再用hashTable对数据库进行insert,update,del操作,注意此时只能用默认的数据库连接”connstr”。

完整的C# Oracle数据库类实例代码如下:

using System;using System.Data;using System.Data.OracleClient;using System.Collections;using System.Reflection;namespace MyOraComm{ /// ConnDbForOracle 的摘要说明。 public class ConnForOracle { protected OracleConnection Connection; private string connectionString; public ConnForOracle() { string connStr; connStr = System.Configuration.ConfigurationSettings.AppSettings[“connStr”].ToString(); connectionString = connStr; Connection = new OracleConnection(connectionString); } #region 带参数的构造函数 /// 带参数的构造函数 /// 数据库联接字符串 public ConnForOracle(string ConnString) { string connStr; connStr = System.Configuration.ConfigurationSettings.AppSettings[ConnString].ToString(); Connection = new OracleConnection(connStr); } #endregion #region 打开数据库 /// 打开数据库 public void OpenConn() { if(this.Connection.State!=ConnectionState.Open) this.Connection.open(); } #endregion #region 关闭数据库联接 /// 关闭数据库联接 public void CloseConn() { if(Connection.State==ConnectionState.Open) Connection.Close(); } #endregion #region 执行sql语句,返回数据到DataSet中 /// 执行sql语句,返回数据到DataSet中 /// sql语句 /// 自定义返回的DataSet表名 /// 返回DataSet public DataSet ReturnDataSet(string sql,string DataSetName) { DataSet dataSet=new DataSet(); OpenConn(); OracleDataAdapter OraDA=new OracleDataAdapter(sql,Connection); OraDA.Fill(dataSet,DataSetName); // CloseConn(); return dataSet; } #endregion #region 执行sql语句,返回带分页功能的dataset /// 执行sql语句,返回带分页功能的dataset /// sql语句 /// 每页显示记录数 /// <当前页/param> /// 返回dataset表名 /// 返回DataSet public DataSet ReturnDataSet(string sql,int PageSize,int CurrPageIndex,PageSize * (CurrPageIndex – 1),PageSize,DataSetName); // CloseConn(); return dataSet; } #endregion #region 执行sql语句,返回 DataReader,用之前一定要先.read()打开,然后才能读到数据 /// 执行sql语句,返回 DataReader,然后才能读到数据 /// sql语句 /// 返回一个OracleDataReader public OracleDataReader ReturnDataReader(String sql) { OpenConn(); OracleCommand command = new OracleCommand(sql,Connection); return command.ExecuteReader(System.Data.CommandBehavior.CloseConnection); } #endregion #region 执行sql语句,返回记录总数数 /// 执行sql语句,返回记录总数数 /// sql语句 /// 返回记录总条数 public int GetRecordCount(string sql) { int recordCount = 0; OpenConn(); OracleCommand command = new OracleCommand(sql,Connection); OracleDataReader dataReader = command.ExecuteReader(); while(dataReader.Read()) { recordCount++; } dataReader.Close(); //CloseConn(); return recordCount; } #endregion #region 取当前序列,条件为seq.nextval或seq.currval /// /// 取当前序列 public decimal GetSeq(string seqstr) { decimal seqnum = 0; string sql=”select “+seqstr+” from dual”; OpenConn(); OracleCommand command = new OracleCommand(sql,Connection); OracleDataReader dataReader = command.ExecuteReader(); if(dataReader.Read()) { seqnum=decimal.Parse(dataReader[0].ToString()); } dataReader.Close(); // CloseConn(); return seqnum; } #endregion #region 执行sql语句,返回所影响的行数 /// 执行sql语句,返回所影响的行数 public int Executesql(string sql) { int Cmd=0; OpenConn(); OracleCommand command = new OracleCommand(sql,Connection); try { Cmd =command.ExecuteNonQuery(); } catch { } finally { //CloseConn(); } return Cmd; } #endregion //==用hashTable对数据库进行insert,注意此时只能用默认的数据库连接”connstr” #region 根据表名及哈稀表自动插入数据库 用法:Insert(“test”,ht) public int Insert(string TableName,Hashtable ht) { OracleParameter[] Parms=new OracleParameter[ht.Count]; IDictionaryEnumerator et = ht.GetEnumerator(); DataTable dt=GetTabType(TableName); System.Data.OracleClient.OracleType otype; int size=0; int i=0; while ( et.MoveNext() ) // 作哈希表循环 { GetoType(et.Key.ToString().ToUpper(),dt,out otype,out size); System.Data.OracleClient.OracleParameter op=MakeParam(“:”+et.Key.ToString(),otype,size,et.Value.ToString()); Parms[i]=op; // 添加sqlParameter对象 i=i+1; } string str_sql=GetInsertsqlbyHt(TableName,ht); // 获得插入sql语句 int val=ExecuteNonQuery(str_sql,Parms); return val; } #endregion #region 根据相关条件对数据库进行更新操作 用法:Update(“test”,”Id=:Id”,ht); public int Update(string TableName,string ht_Where,Hashtable ht) { OracleParameter[] Parms=new OracleParameter[ht.Count]; IDictionaryEnumerator et = ht.GetEnumerator(); DataTable dt=GetTabType(TableName); System.Data.OracleClient.OracleType otype; int size=0; int i=0; // 作哈希表循环 while ( et.MoveNext() ) { GetoType(et.Key.ToString().ToUpper(),et.Value.ToString()); Parms[i]=op; // 添加sqlParameter对象 i=i+1; } string str_sql=GetUpdatesqlbyHt(TableName,ht_Where,Parms); return val; } #endregion #region del操作,注意此处条件个数与hash里参数个数应该一致 用法:Del(“test”,ht) public int Del(string TableName,Hashtable ht) { OracleParameter[] Parms=new OracleParameter[ht.Count]; IDictionaryEnumerator et = ht.GetEnumerator(); DataTable dt=GetTabType(TableName); System.Data.OracleClient.OracleType otype; int i=0; int size=0; // 作哈希表循环 while ( et.MoveNext() ) { GetoType(et.Key.ToString().ToUpper(),et.Value.ToString()); Parms[i]=op; // 添加sqlParameter对象 i=i+1; } string str_sql=GetDelsqlbyHt(TableName,ht); // 获得删除sql语句 int val=ExecuteNonQuery(str_sql,Parms); return val; } #endregion // ========上面三个操作的内部调用函数================== #region 根据哈稀表及表名自动生成相应insert语句(参数类型的) /// 根据哈稀表及表名自动生成相应insert语句 /// 要插入的表名 /// 哈稀表 /// 返回sql语句 public static string GetInsertsqlbyHt(string TableName,Hashtable ht) { string str_sql=””; int i=0; int ht_Count=ht.Count; // 哈希表个数 IDictionaryEnumerator myEnumerator = ht.GetEnumerator(); string before=””; string behide=””; while ( myEnumerator.MoveNext() ) { if (i==0) { before=”(“+myEnumerator.Key; } else if (i+1==ht_Count) { before=before+”,”+myEnumerator.Key+”)”; } else { before=before+”,”+myEnumerator.Key; } i=i+1; } behide=” Values”+before.Replace(“,”,:”).Replace(“(“,”(:”); str_sql=”Insert into “+TableName+before+behide; return str_sql; } #endregion #region 根据表名,where条件,哈稀表自动生成更新语句(参数类型的) public static string GetUpdatesqlbyHt(string Table,Hashtable ht) { string str_sql=””; int i=0; int ht_Count=ht.Count; // 哈希表个数 IDictionaryEnumerator myEnumerator = ht.GetEnumerator(); while ( myEnumerator.MoveNext() ) { if (i==0) { if (ht_Where.ToString().ToLower().IndexOf((myEnumerator.Key+”=:”+myEnumerator.Key).ToLower())==-1) { str_sql=myEnumerator.Key+”=:”+myEnumerator.Key; } } else { if (ht_Where.ToString().ToLower().IndexOf((“:”+myEnumerator.Key+” “).ToLower())==-1) { str_sql=str_sql+”,”+myEnumerator.Key+”=:”+myEnumerator.Key; } } i=i+1; } if (ht_Where==null || ht_Where.Replace(” “,””)==””) // 更新时候没有条件 { str_sql=”update “+Table+” set “+str_sql; } else { str_sql=”update “+Table+” set “+str_sql+” where “+ht_Where; } str_sql=str_sql.Replace(“set,”set “).Replace(“update,”update “); return str_sql; } #endregion #region 根据表名,where条件,哈稀表自动生成del语句(参数类型的) public static string GetDelsqlbyHt(string Table,Hashtable ht) { string str_sql=””; int i=0; int ht_Count=ht.Count; // 哈希表个数 IDictionaryEnumerator myEnumerator = ht.GetEnumerator(); while ( myEnumerator.MoveNext() ) { if (i==0) { if (ht_Where.ToString().ToLower().IndexOf((myEnumerator.Key+”=:”+myEnumerator.Key).ToLower())==-1) { str_sql=myEnumerator.Key+”=:”+myEnumerator.Key; } } else { if (ht_Where.ToString().ToLower().IndexOf((“:”+myEnumerator.Key+” “).ToLower())==-1) { str_sql=str_sql+”,””)==””) // 更新时候没有条件 { str_sql=”Delete “+Table; } else { str_sql=”Delete “+Table+” where “+ht_Where; } return str_sql; } #endregion #region 生成oracle参数 /// /// 生成oracle参数 /// 字段名 /// 数据类型 /// 数据大小 /// 值 public static OracleParameter MakeParam(string ParamName,System.Data.OracleClient.OracleType otype,int size,Object Value) { OracleParameter para=new OracleParameter(ParamName,Value); para.OracleType=otype; para.Size=size; return para; } #endregion #region 生成oracle参数 public static OracleParameter MakeParam(string ParamName,string Value) { return new OracleParameter(ParamName,Value); } #endregion #region 根据表结构字段的类型和长度拼装oracle sql语句参数 public static void GetoType(string key,DataTable dt,out System.Data.OracleClient.OracleType otype,out int size) { DataView dv=dt.DefaultView; dv.RowFilter=”column_name='”+key+”‘”; string fType=dv[0][“data_type”].ToString().ToUpper(); switch (fType) { case “DATE”: otype= OracleType.DateTime; size=int.Parse(dv[0][“data_length”].ToString()); break; case “CHAR”: otype= OracleType.Char; size=int.Parse(dv[0][“data_length”].ToString()); break; case “LONG”: otype= OracleType.Double; size=int.Parse(dv[0][“data_length”].ToString()); break; case “NVARCHAR2”: otype= OracleType.NVarChar; size=int.Parse(dv[0][“data_length”].ToString()); break; case “VARCHAR2”: otype= OracleType.NVarChar; size=int.Parse(dv[0][“data_length”].ToString()); break; default: otype= OracleType.NVarChar; size=100; break; } } #endregion #region动态 取表里字段的类型和长度,此处没有动态用到connstr,是默认的!by/文少 public System.Data.DataTable GetTabType(string tabnale) { string sql=”select column_name,data_type,data_length from all_tab_columns where table_name='”+tabnale.ToUpper()+”‘”; OpenConn(); return (ReturnDataSet(sql,”dv”)).Tables[0]; } #endregion #region 执行sql语句 public int ExecuteNonQuery(string cmdText,params OracleParameter[] cmdParms) { OracleCommand cmd = new OracleCommand(); OpenConn(); cmd.Connection=Connection; cmd.CommandText = cmdText; if (cmdParms != null) { foreach (OracleParameter parm in cmdParms) cmd.Parameters.Add(parm); } int val = cmd.ExecuteNonQuery(); cmd.Parameters.Clear(); //conn.CloseConn(); return val; } #endregion } }

使用时可将上述代码保存成oracle_dbconn.cs文件,再进行调用。