现在我要做access和SQL数据库连接查询,已经能从这两种数据库进行连接查询了,但又有很多问题,比如在Sql语句中怎样去掉如字段textcolumn中的;号,还有操作sql数据库可以用sqldatareader,那么操作access数据库能用datareader吗?能用的话用哪种datareader,怎么用?说祥细点
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在存入之前可以采用textcolumn.replace(";","");
使用OleDbDataReader就可以了,using System.Data.OleDb;
==================AccessHelper.cs
using System;
using System.Data;
using System.Configuration;
using System.Web;
using System.Data.OleDb;
using System.Collections;
using System.Text;namespace DBUtility
{
/// <summary>
/// AcceHelper 的摘要说明
/// </summary>
public static class AccessHelper
{
//数据库连接字符串
public static readonly string Connection = "Provider=Microsoft.Jet.OLEDB.4.0;Persist Security Info=true;Data Source="
+ HttpContext.Current.Request.PhysicalApplicationPath
+ System.Configuration.ConfigurationManager.ConnectionStrings["ConnectionString"].ConnectionString;
// 用于缓存参数的HASH表
private static Hashtable parmCache = Hashtable.Synchronized(new Hashtable()); /// <summary>
/// 给定连接的数据库用假设参数执行一个sql命令(不返回数据集)
/// </summary>
/// <param name="connectionString">一个有效的连接字符串</param>
/// <param name="commandText">存储过程名称或者sql命令语句</param>
/// <param name="commandParameters">执行命令所用参数的集合</param>
/// <returns>执行命令所影响的行数</returns>
public static int ExecuteNonQuery(string connectionString, string cmdText, params OleDbParameter[] commandParameters)
{
OleDbCommand cmd = new OleDbCommand();
using (OleDbConnection conn = new OleDbConnection(connectionString))
{
PrepareCommand(cmd, conn, null, cmdText, commandParameters);
int val = cmd.ExecuteNonQuery();
cmd.Parameters.Clear();
return val;
}
}
/// <summary>
/// 用现有的数据库连接执行一个sql命令(不返回数据集)
/// </summary>
/// <res>
///举例:
/// int result = ExecuteNonQuery(connString, "PublishOrders", new OleDbParameter("@prodid", 24));
/// </res>
/// <param name="conn">一个现有的数据库连接</param>
/// <param name="commandText">存储过程名称或者sql命令语句</param>
/// <param name="commandParameters">执行命令所用参数的集合</param>
/// <returns>执行命令所影响的行数</returns>
public static int ExecuteNonQuery(OleDbConnection connection, string cmdText, params OleDbParameter[] commandParameters)
{
OleDbCommand cmd = new OleDbCommand();
PrepareCommand(cmd, connection, null, cmdText, commandParameters);
int val = cmd.ExecuteNonQuery();
cmd.Parameters.Clear();
return val;
}
/// <summary>
/// 用执行的数据库连接执行一个返回数据集的sql命令
/// </summary>
/// <res>
/// 举例:
/// OleDbDataReader r = ExecuteReader(connString, "PublishOrders", new OleDbParameter("@prodid", 24));
/// </res>
/// <param name="connectionString">一个有效的连接字符串</param>
/// <param name="commandText">存储过程名称或者sql命令语句</param>
/// <param name="commandParameters">执行命令所用参数的集合</param>
/// <returns>包含结果的读取器</returns>
public static OleDbDataReader ExecuteReader(string connectionString, string cmdText, params OleDbParameter[] commandParameters)
{
//创建一个SqlCommand对象
OleDbCommand cmd = new OleDbCommand();
//创建一个SqlConnection对象
OleDbConnection conn = new OleDbConnection(connectionString);
//在这里我们用一个try/catch结构执行sql文本命令/存储过程,因为如果这个方法产生一个异常我们要关闭连接,因为没有读取器存在,
//因此commandBehaviour.CloseConnection 就不会执行
try
{
//调用 PrepareCommand 方法,对 SqlCommand 对象设置参数
PrepareCommand(cmd, conn, null, cmdText, commandParameters);
//调用 SqlCommand 的 ExecuteReader 方法
OleDbDataReader reader = cmd.ExecuteReader(CommandBehavior.CloseConnection);
//清除参数
cmd.Parameters.Clear();
return reader;
}
catch
{
//关闭连接,抛出异常
conn.Close();
throw;
}
}
public static DataSet ExecuteDataSet(string connectionString, string strSQL)
{
OleDbConnection conn = new OleDbConnection(AccessHelper.Connection);
DataSet ds = null;
try
{
ds = new DataSet();
OleDbDataAdapter da = new OleDbDataAdapter(strSQL, conn); da.Fill(ds);
return ds;
}
catch (Exception ex)
{ throw ex;
}
finally
{
ds.Dispose();
conn.Close();
}
} public static DataSet ExecuteDataSet(string connectionString, string strSQL, params OleDbParameter[] commandParameters)
{
OleDbConnection conn = new OleDbConnection(AccessHelper.Connection);
DataSet ds = null;
try
{
ds = new DataSet();
OleDbDataAdapter da = new OleDbDataAdapter(strSQL, conn);
foreach (OleDbParameter parm in commandParameters)
da.SelectCommand.Parameters.Add(parm);
da.Fill(ds);
return ds;
}
catch (Exception ex)
{ throw ex;
}
finally
{
conn.Close();
}
} /// <summary>
/// 用指定的数据库连接字符串执行一个命令并返回一个数据集的第一列
/// </summary>
/// <res>
///例如:
/// Object obj = ExecuteScalar(connString, "PublishOrders", new OleDbParameter("@prodid", 24));
/// </res>
///<param name="connectionString">一个有效的连接字符串</param>
/// <param name="commandText">存储过程名称或者sql命令语句</param>
/// <param name="commandParameters">执行命令所用参数的集合</param>
/// <returns>用 Convert.To{Type}把类型转换为想要的 </returns>
public static object ExecuteScalar(string connectionString, string cmdText, params OleDbParameter[] commandParameters)
{
OleDbCommand cmd = new OleDbCommand();
using (OleDbConnection connection = new OleDbConnection(connectionString))
{
PrepareCommand(cmd, connection, null, cmdText, commandParameters);
object val = cmd.ExecuteScalar();
cmd.Parameters.Clear();
return val;
}
} /// <summary>
/// 用指定的数据库连接执行一个命令并返回一个数据集的第一列
/// </summary>
/// <res>
/// 例如:
/// Object obj = ExecuteScalar(connString, "PublishOrders", new OleDbParameter("@prodid", 24));
/// </res>
/// <param name="conn">一个存在的数据库连接</param>
/// <param name="commandText">存储过程名称或者sql命令语句</param>
/// <param name="commandParameters">执行命令所用参数的集合</param>
/// <returns>用 Convert.To{Type}把类型转换为想要的 </returns>
public static object ExecuteScalar(OleDbConnection connection, string cmdText, params OleDbParameter[] commandParameters)
{
OleDbCommand cmd = new OleDbCommand();
PrepareCommand(cmd, connection, null, cmdText, commandParameters);
object val = cmd.ExecuteScalar();
cmd.Parameters.Clear();
return val;
} /// <summary>
/// 将参数集合添加到缓存
/// </summary>
/// <param name="cacheKey">添加到缓存的变量</param>
/// <param name="cmdParms">一个将要添加到缓存的sql参数集合</param>
public static void CacheParameters(string cacheKey, params OleDbParameter[] commandParameters)
{
parmCache[cacheKey] = commandParameters;
} /// <summary>
/// 找回缓存参数集合
/// </summary>
/// <param name="cacheKey">用于找回参数的关键字</param>
/// <returns>缓存的参数集合</returns>
public static OleDbParameter[] GetCachedParameters(string cacheKey)
{
OleDbParameter[] cachedParms = (OleDbParameter[])parmCache[cacheKey];
if (cachedParms == null)
return null;
OleDbParameter[] clonedParms = new OleDbParameter[cachedParms.Length];
for (int i = 0, j = cachedParms.Length; i < j; i++)
clonedParms = (OleDbParameter[])((ICloneable)cachedParms).Clone();
return clonedParms;
} /// <summary>
/// 准备执行一个命令
/// </summary>
/// <param name="cmd">sql命令</param>
/// <param name="conn">Sql连接</param>
/// <param name="trans">Sql事务</param>
/// <param name="cmdText">命令文本,例如:Select * from Products</param>
/// <param name="cmdParms">执行命令的参数</param>
private static void PrepareCommand(OleDbCommand cmd, OleDbConnection conn, OleDbTransaction trans, string cmdText, OleDbParameter[] cmdParms)
{
//判断连接的状态。如果是关闭状态,则打开
if (conn.State != ConnectionState.Open)
conn.Open();
//cmd属性赋值
cmd.Connection = conn;
cmd.CommandText = cmdText;
//是否需要用到事务处理
if (trans != null)
cmd.Transaction = trans;
cmd.CommandType = CommandType.Text;
//添加cmd需要的存储过程参数
if (cmdParms != null)
{
foreach (OleDbParameter parm in cmdParms)
cmd.Parameters.Add(parm);
}
}
}
}
去掉;号直接replace即可.
access可以用oledbdatareader,用法基本一样.