在偶尔的情况下会出现,不知道怎么解决了,求助高手
using System;
using System.Collections.Generic;
using System.Text;
using System.Data;
using System.Data.OracleClient;
using System.Configuration;
using UserSystem.Public;namespace UserSystem.Data.DBHelper
{
public class OracleHelper
{
private static OracleConnection conn = new OracleConnection();
private static OracleCommand cmd = new OracleCommand();
private static List<OracleParameter> para = new List<OracleParameter>();
private static String cstr;
private static OracleTransaction trans; #region 构造函数
/// <summary>
/// 构造函数(使用默认的数据库链接串)
/// </summary>
public OracleHelper()
{
main(ConfigurationManager.ConnectionStrings["Default"].ConnectionString);
}
/// <summary>
/// 构造函数
/// </summary>
/// <param name="_s">数据库链接串</param>
public OracleHelper(String _s)
{
main(_s);
}
/// <summary>
/// 关闭函数
/// </summary>
public void close()
{
conn.Close();
}
#endregion #region 相关设置
/// <summary>
/// 初始化设置
/// </summary>
/// <param name="_s">ConnectionStrings</param>
private static void main(String _s)
{
cstr = _s;
if (conn.State == ConnectionState.Open)
{
conn.Close();
}
conn.ConnectionString = cstr;
conn.Open();
cmd.Connection = conn;
cmd.Transaction = null;
cmd.CommandType = CommandType.Text;
}
#endregion #region cmd对象Parameters设置
/// <summary>
/// 清除cmd对象的Parameters
/// </summary>
public void paraClear()
{
para.Clear();
}
/// <summary>
/// 设置cmd对象的Parameters
/// </summary>
/// <param name="_name">参数名称</param>
/// <param name="_OracleType">参数类型</param>
/// <param name="_value">值</param>
/// <param name="_length">长度</param>
public void paraAdd(String _name, String _OracleType, String _value, int _length)
{
para.Add(new OracleParameter(_name, prv_OracleType(_OracleType), _length));
para[para.Count - 1].Value = publicApp.GetByLenB(_value, _length);
}
#endregion #region 数据库操作
/// <summary>
/// Query
/// </summary>
/// <param name="_SQLString">SQL语句</param>
/// <returns>DataSet</returns>
public DataSet Query(String _SQLString)
{ DataSet _ds = new DataSet(); PrepareCommand(_SQLString, para);
OracleDataAdapter da = new OracleDataAdapter(cmd);
da.Fill(_ds); //错误在这里
return _ds;
}
#endregion #region 私有方法
/// <summary>
/// 为cmd对象设置Parameters
/// </summary>
/// <param name="_SQLString">SQL语句</param>
private void PrepareCommand(string _cmdText, List<OracleParameter> _cmdParms)
{
cmd.CommandText = _cmdText;
cmd.Parameters.Clear();
if (_cmdParms != null)
{
foreach (OracleParameter __parm in _cmdParms)
cmd.Parameters.Add(__parm);
}
}
/// <summary>
/// 翻译字段类型
/// </summary>
/// <param name="_s">类型值</param>
/// <returns>OracleType</returns>
private OracleType prv_OracleType(String _s)
{
switch (_s)
{
case "number":
return OracleType.Number;
break;
case "datetime":
return OracleType.DateTime;
break;
case "varchar":
return OracleType.VarChar;
break;
case "long":
return OracleType.LongVarChar;
break;
case "blob":
return OracleType.Blob;
break;
default:
return OracleType.VarChar;
break;
}
}
#endregion }
}
using System;
using System.Collections.Generic;
using System.Text;
using System.Data;
using System.Data.OracleClient;
using System.Configuration;
using UserSystem.Public;namespace UserSystem.Data.DBHelper
{
public class OracleHelper
{
private static OracleConnection conn = new OracleConnection();
private static OracleCommand cmd = new OracleCommand();
private static List<OracleParameter> para = new List<OracleParameter>();
private static String cstr;
private static OracleTransaction trans; #region 构造函数
/// <summary>
/// 构造函数(使用默认的数据库链接串)
/// </summary>
public OracleHelper()
{
main(ConfigurationManager.ConnectionStrings["Default"].ConnectionString);
}
/// <summary>
/// 构造函数
/// </summary>
/// <param name="_s">数据库链接串</param>
public OracleHelper(String _s)
{
main(_s);
}
/// <summary>
/// 关闭函数
/// </summary>
public void close()
{
conn.Close();
}
#endregion #region 相关设置
/// <summary>
/// 初始化设置
/// </summary>
/// <param name="_s">ConnectionStrings</param>
private static void main(String _s)
{
cstr = _s;
if (conn.State == ConnectionState.Open)
{
conn.Close();
}
conn.ConnectionString = cstr;
conn.Open();
cmd.Connection = conn;
cmd.Transaction = null;
cmd.CommandType = CommandType.Text;
}
#endregion #region cmd对象Parameters设置
/// <summary>
/// 清除cmd对象的Parameters
/// </summary>
public void paraClear()
{
para.Clear();
}
/// <summary>
/// 设置cmd对象的Parameters
/// </summary>
/// <param name="_name">参数名称</param>
/// <param name="_OracleType">参数类型</param>
/// <param name="_value">值</param>
/// <param name="_length">长度</param>
public void paraAdd(String _name, String _OracleType, String _value, int _length)
{
para.Add(new OracleParameter(_name, prv_OracleType(_OracleType), _length));
para[para.Count - 1].Value = publicApp.GetByLenB(_value, _length);
}
#endregion #region 数据库操作
/// <summary>
/// Query
/// </summary>
/// <param name="_SQLString">SQL语句</param>
/// <returns>DataSet</returns>
public DataSet Query(String _SQLString)
{ DataSet _ds = new DataSet(); PrepareCommand(_SQLString, para);
OracleDataAdapter da = new OracleDataAdapter(cmd);
da.Fill(_ds); //错误在这里
return _ds;
}
#endregion #region 私有方法
/// <summary>
/// 为cmd对象设置Parameters
/// </summary>
/// <param name="_SQLString">SQL语句</param>
private void PrepareCommand(string _cmdText, List<OracleParameter> _cmdParms)
{
cmd.CommandText = _cmdText;
cmd.Parameters.Clear();
if (_cmdParms != null)
{
foreach (OracleParameter __parm in _cmdParms)
cmd.Parameters.Add(__parm);
}
}
/// <summary>
/// 翻译字段类型
/// </summary>
/// <param name="_s">类型值</param>
/// <returns>OracleType</returns>
private OracleType prv_OracleType(String _s)
{
switch (_s)
{
case "number":
return OracleType.Number;
break;
case "datetime":
return OracleType.DateTime;
break;
case "varchar":
return OracleType.VarChar;
break;
case "long":
return OracleType.LongVarChar;
break;
case "blob":
return OracleType.Blob;
break;
default:
return OracleType.VarChar;
break;
}
}
#endregion }
}
这样用静态的属性,在多线程环境下不报错才怪。把所有静态的field改成helper的字段。不要用静态变量。
连parameter你都用静态变量来做,怎么能不出错?当你一个线程去fill还没完成的时候,第二个线程来clear你的paramters list,你说结果会怎样?
Conn和Command都是静态在数据访问层一定是不行的.using System;
using System.Configuration;
using System.Data;
using System.Data.OracleClient;
using System.Collections;namespace PetShop.DBUtility { /// <summary>
/// A helper class used to execute queries against an Oracle database
/// </summary>
public abstract class OracleHelper { // Read the connection strings from the configuration file
public static readonly string ConnectionStringLocalTransaction = ConfigurationManager.ConnectionStrings["OraConnString1"].ConnectionString;
public static readonly string ConnectionStringInventoryDistributedTransaction = ConfigurationManager.ConnectionStrings["OraConnString2"].ConnectionString;
public static readonly string ConnectionStringOrderDistributedTransaction = ConfigurationManager.ConnectionStrings["OraConnString3"].ConnectionString;
public static readonly string ConnectionStringProfile = ConfigurationManager.ConnectionStrings["OraProfileConnString"].ConnectionString;
public static readonly string ConnectionStringMembership = ConfigurationManager.ConnectionStrings["OraMembershipConnString"].ConnectionString; //Create a hashtable for the parameter cached
private static Hashtable parmCache = Hashtable.Synchronized(new Hashtable()); /// <summary>
/// Execute a database query which does not include a select
/// </summary>
/// <param name="connString">Connection string to database</param>
/// <param name="cmdType">Command type either stored procedure or SQL</param>
/// <param name="cmdText">Acutall SQL Command</param>
/// <param name="commandParameters">Parameters to bind to the command</param>
/// <returns></returns>
public static int ExecuteNonQuery(string connectionString, CommandType cmdType, string cmdText, params OracleParameter[] commandParameters) {
// Create a new Oracle command
OracleCommand cmd = new OracleCommand(); //Create a connection
using (OracleConnection connection = new OracleConnection(connectionString)) { //Prepare the command
PrepareCommand(cmd, connection, null, cmdType, cmdText, commandParameters); //Execute the command
int val = cmd.ExecuteNonQuery();
cmd.Parameters.Clear();
return val;
}
} /// <summary>
/// Execute an OracleCommand (that returns no resultset) against an existing database transaction
/// using the provided parameters.
/// </summary>
/// <res>
/// e.g.:
/// int result = ExecuteNonQuery(trans, CommandType.StoredProcedure, "PublishOrders", new OracleParameter(":prodid", 24));
/// </res>
/// <param name="trans">an existing database transaction</param>
/// <param name="commandType">the CommandType (stored procedure, text, etc.)</param>
/// <param name="commandText">the stored procedure name or PL/SQL command</param>
/// <param name="commandParameters">an array of OracleParamters used to execute the command</param>
/// <returns>an int representing the number of rows affected by the command</returns>
public static int ExecuteNonQuery(OracleTransaction trans, CommandType cmdType, string cmdText, params OracleParameter[] commandParameters) {
OracleCommand cmd = new OracleCommand();
PrepareCommand(cmd, trans.Connection, trans, cmdType, cmdText, commandParameters);
int val = cmd.ExecuteNonQuery();
cmd.Parameters.Clear();
return val;
} /// <summary>
/// Execute an OracleCommand (that returns no resultset) against an existing database connection
/// using the provided parameters.
/// </summary>
/// <res>
/// e.g.:
/// int result = ExecuteNonQuery(connString, CommandType.StoredProcedure, "PublishOrders", new OracleParameter(":prodid", 24));
/// </res>
/// <param name="conn">an existing database connection</param>
/// <param name="commandType">the CommandType (stored procedure, text, etc.)</param>
/// <param name="commandText">the stored procedure name or PL/SQL command</param>
/// <param name="commandParameters">an array of OracleParamters used to execute the command</param>
/// <returns>an int representing the number of rows affected by the command</returns>
public static int ExecuteNonQuery(OracleConnection connection, CommandType cmdType, string cmdText, params OracleParameter[] commandParameters) { OracleCommand cmd = new OracleCommand(); PrepareCommand(cmd, connection, null, cmdType, cmdText, commandParameters);
int val = cmd.ExecuteNonQuery();
cmd.Parameters.Clear();
return val;
} /// <summary>
/// Execute a select query that will return a result set
/// </summary>
/// <param name="connString">Connection string</param>
//// <param name="commandType">the CommandType (stored procedure, text, etc.)</param>
/// <param name="commandText">the stored procedure name or PL/SQL command</param>
/// <param name="commandParameters">an array of OracleParamters used to execute the command</param>
/// <returns></returns>
public static OracleDataReader ExecuteReader(string connectionString, CommandType cmdType, string cmdText, params OracleParameter[] commandParameters) { //Create the command and connection
OracleCommand cmd = new OracleCommand();
OracleConnection conn = new OracleConnection(connectionString); try {
//Prepare the command to execute
PrepareCommand(cmd, conn, null, cmdType, cmdText, commandParameters); //Execute the query, stating that the connection should close when the resulting datareader has been read
OracleDataReader rdr = cmd.ExecuteReader(CommandBehavior.CloseConnection);
cmd.Parameters.Clear();
return rdr; }
catch { //If an error occurs close the connection as the reader will not be used and we expect it to close the connection
conn.Close();
throw;
}
}
/// <summary>
/// Execute an OracleCommand that returns the first column of the first record against the database specified in the connection string
/// using the provided parameters.
/// </summary>
/// <res>
/// e.g.:
/// Object obj = ExecuteScalar(connString, CommandType.StoredProcedure, "PublishOrders", new OracleParameter(":prodid", 24));
/// </res>
/// <param name="connectionString">a valid connection string for a SqlConnection</param>
/// <param name="commandType">the CommandType (stored procedure, text, etc.)</param>
/// <param name="commandText">the stored procedure name or PL/SQL command</param>
/// <param name="commandParameters">an array of OracleParamters used to execute the command</param>
/// <returns>An object that should be converted to the expected type using Convert.To{Type}</returns>
public static object ExecuteScalar(string connectionString, CommandType cmdType, string cmdText, params OracleParameter[] commandParameters) {
OracleCommand cmd = new OracleCommand(); using (OracleConnection conn = new OracleConnection(connectionString)) {
PrepareCommand(cmd, conn, null, cmdType, cmdText, commandParameters);
object val = cmd.ExecuteScalar();
cmd.Parameters.Clear();
return val;
}
} /// <summary>
/// Execute a OracleCommand (that returns a 1x1 resultset) against the specified SqlTransaction
/// using the provided parameters.
/// </summary>
/// <param name="transaction">A valid SqlTransaction</param>
/// <param name="commandType">The CommandType (stored procedure, text, etc.)</param>
/// <param name="commandText">The stored procedure name or PL/SQL command</param>
/// <param name="commandParameters">An array of OracleParamters used to execute the command</param>
/// <returns>An object containing the value in the 1x1 resultset generated by the command</returns>
public static object ExecuteScalar(OracleTransaction transaction, CommandType commandType, string commandText, params OracleParameter[] commandParameters) {
if(transaction == null)
throw new ArgumentNullException("transaction");
if(transaction != null && transaction.Connection == null)
throw new ArgumentException("The transaction was rollbacked or commited, please provide an open transaction.", "transaction"); // Create a command and prepare it for execution
OracleCommand cmd = new OracleCommand(); PrepareCommand(cmd, transaction.Connection, transaction, commandType, commandText, commandParameters); // Execute the command & return the results
object retval = cmd.ExecuteScalar(); // Detach the SqlParameters from the command object, so they can be used again
cmd.Parameters.Clear();
return retval;
} /// <summary>
/// Execute an OracleCommand that returns the first column of the first record against an existing database connection
/// using the provided parameters.
/// </summary>
/// <res>
/// e.g.:
/// Object obj = ExecuteScalar(conn, CommandType.StoredProcedure, "PublishOrders", new OracleParameter(":prodid", 24));
/// </res>
/// <param name="conn">an existing database connection</param>
/// <param name="commandType">the CommandType (stored procedure, text, etc.)</param>
/// <param name="commandText">the stored procedure name or PL/SQL command</param>
/// <param name="commandParameters">an array of OracleParamters used to execute the command</param>
/// <returns>An object that should be converted to the expected type using Convert.To{Type}</returns>
public static object ExecuteScalar(OracleConnection connectionString, CommandType cmdType, string cmdText, params OracleParameter[] commandParameters) {
OracleCommand cmd = new OracleCommand(); PrepareCommand(cmd, connectionString, null, cmdType, cmdText, commandParameters);
object val = cmd.ExecuteScalar();
cmd.Parameters.Clear();
return val;
} /// <summary>
/// Add a set of parameters to the cached
/// </summary>
/// <param name="cacheKey">Key value to look up the parameters</param>
/// <param name="commandParameters">Actual parameters to cached</param>
public static void CacheParameters(string cacheKey, params OracleParameter[] commandParameters) {
parmCache[cacheKey] = commandParameters;
} /// <summary>
/// Fetch parameters from the cache
/// </summary>
/// <param name="cacheKey">Key to look up the parameters</param>
/// <returns></returns>
public static OracleParameter[] GetCachedParameters(string cacheKey) {
OracleParameter[] cachedParms = (OracleParameter[])parmCache[cacheKey]; if (cachedParms == null)
return null; // If the parameters are in the cache
OracleParameter[] clonedParms = new OracleParameter[cachedParms.Length]; // return a copy of the parameters
for (int i = 0, j = cachedParms.Length; i < j; i++)
clonedParms[i] = (OracleParameter)((ICloneable)cachedParms[i]).Clone(); return clonedParms;
} /// <summary>
/// Internal function to prepare a command for execution by the database
/// </summary>
/// <param name="cmd">Existing command object</param>
/// <param name="conn">Database connection object</param>
/// <param name="trans">Optional transaction object</param>
/// <param name="cmdType">Command type, e.g. stored procedure</param>
/// <param name="cmdText">Command test</param>
/// <param name="commandParameters">Parameters for the command</param>
private static void PrepareCommand(OracleCommand cmd, OracleConnection conn, OracleTransaction trans, CommandType cmdType, string cmdText, OracleParameter[] commandParameters) { //Open the connection if required
if (conn.State != ConnectionState.Open)
conn.Open(); //Set up the command
cmd.Connection = conn;
cmd.CommandText = cmdText;
cmd.CommandType = cmdType; //Bind it to the transaction if it exists
if (trans != null)
cmd.Transaction = trans; // Bind the parameters passed in
if (commandParameters != null) {
foreach (OracleParameter parm in commandParameters)
cmd.Parameters.Add(parm);
}
} /// <summary>
/// Converter to use boolean data type with Oracle
/// </summary>
/// <param name="value">Value to convert</param>
/// <returns></returns>
public static string OraBit(bool value) {
if(value)
return "Y";
else
return "N";
} /// <summary>
/// Converter to use boolean data type with Oracle
/// </summary>
/// <param name="value">Value to convert</param>
/// <returns></returns>
public static bool OraBool(string value) {
if(value.Equals("Y"))
return true;
else
return false;
}
}
}