C#.NET操作数据库通用类

下面给出了一个C#操作MS SQL Server 数据库的通用类，通过该类可以对数据库进行任何操作，包括执行SQL语句、执行存储过程。以下是其详细实现过程，希望大家共同修改优化之。稍后将介绍如何使用它实现N层的程序设计。

配置web.config文件的链接参数

<appSettings>
<!--
connStr参数设置，事例说明：
（1）Sql server数据库，例如“server=local;database=test;uid=sa;pwd=;”
（2）Access数据库，例如“data/ex.mdb; user id='admin';Jet OLEDB:database password='admin';”
-->
<add key="connStr" value="server=127.0.0.1;database=DbName;uid=sa;pwd=;" />
</appSettings>

C#代码

using System;
using System.Data;
using System.Data.SqlClient;

namespace Com.LXJ.Database
{
/// <summary>
/// ConnDB 的摘要说明。
/// </summary>
public class ConnDB
{
protected SqlConnection Connection;
private string connectionString;

/// <summary>
/// 默认构造函数
/// </summary>
public ConnDB()
{
string connStr;
connStr = System.Configuration.ConfigurationSettings.AppSettings["connStr"].ToString();

connectionString = connStr;
Connection = new SqlConnection(connectionString);
}

/// <summary>
/// 带参数的构造函数
/// </summary>
/// <param name="newConnectionString">数据库联接字符串</param>
public ConnDB(string newConnectionString)
{
connectionString = newConnectionString;
Connection = new SqlConnection(connectionString);
}

/// <summary>
/// 完成SqlCommand对象的实例化
/// </summary>
/// <param name="storedProcName"></param>
/// <param name="parameters"></param>
/// <returns></returns>
private SqlCommand BuildCommand(string storedProcName,IDataParameter[] parameters)
{
SqlCommand command = BuildQueryCommand(storedProcName,parameters);
command.Parameters.Add(new SqlParameter("ReturnValue",SqlDbType.Int,4,ParameterDirection.ReturnValue,false,0,0,string.Empty,DataRowVersion.Default,null));
return command;
}

/// <summary>
/// 创建新的SQL命令对象(存储过程)
/// </summary>
/// <param name="storedProcName"></param>
/// <param name="parameters"></param>
/// <returns></returns>
private SqlCommand BuildQueryCommand(string storedProcName,IDataParameter[] parameters)
{
SqlCommand command = new SqlCommand(storedProcName,Connection);
command.CommandType = CommandType.StoredProcedure;
foreach (SqlParameter parameter in parameters)
{
command.Parameters.Add(parameter);
}
return command;
}

/// <summary>
/// 执行存储过程,无返回值
/// </summary>
/// <param name="storedProcName"></param>
/// <param name="parameters"></param>
public void ExecuteProcedure(string storedProcName,IDataParameter[] parameters)
{
Connection.Open();
SqlCommand command;
command=BuildQueryCommand(storedProcName,parameters);
command.ExecuteNonQuery();
Connection.Close();
}

/// <summary>
/// 执行存储过程，返回执行操作影响的行数目
/// </summary>
/// <param name="storedProcName"></param>
/// <param name="parameters"></param>
/// <param name="rowsAffected"></param>
/// <returns></returns>
public int RunProcedure(string storedProcName,IDataParameter[] parameters,out int rowsAffected)
{
int result;
Connection.Open();
SqlCommand command = BuildCommand(storedProcName,parameters);
rowsAffected = command.ExecuteNonQuery();
result = (int)command.Parameters["ReturnValue"].Value;
Connection.Close();

return result;
}

/// <summary>
/// 重载RunProcedure把执行存储过程的结果放在SqlDataReader中
/// </summary>
/// <param name="storedProcName"></param>
/// <param name="parameters"></param>
/// <returns></returns>
public SqlDataReader RunProcedure(string storedProcName,IDataParameter[] parameters)
{
SqlDataReader returnReader;
Connection.Open();
SqlCommand command = BuildQueryCommand(storedProcName,parameters);
command.CommandType = CommandType.StoredProcedure;
returnReader = command.ExecuteReader(CommandBehavior.CloseConnection);
return returnReader;
}

/// <summary>
/// 重载RunProcedure把执行存储过程的结果存储在DataSet中和表tableName为可选参数
/// </summary>
/// <param name="storedProcName"></param>
/// <param name="parameters"></param>
/// <param name="tableName"></param>
/// <returns></returns>
public DataSet RunProcedure(string storedProcName,IDataParameter[] parameters,params string[] tableName)
{
DataSet dataSet = new DataSet();
Connection.Open();
SqlDataAdapter sqlDA = new SqlDataAdapter();
sqlDA.SelectCommand = BuildQueryCommand(storedProcName,parameters);
string flag;
flag = "";
for(int i=0;i<tableName.Length;i++)
flag = tableName[i];
if (flag!="")
sqlDA.Fill(dataSet,tableName[0]);
else
sqlDA.Fill(dataSet);
Connection.Close();
return dataSet;
}

/// <summary>
/// 执行SQL语句，返回数据到DataSet中
/// </summary>
/// <param name="sql"></param>
/// <returns></returns>
public DataSet ReturnDataSet(string sql)
{
DataSet dataSet=new DataSet();
Connection.Open();
SqlDataAdapter sqlDA=new SqlDataAdapter(sql,Connection);
sqlDA.Fill(dataSet,"objDataSet");
Connection.Close();
return dataSet;
}

/// <summary>
/// 执行SQL语句，返回 DataReader
/// </summary>
/// <param name="sql"></param>
/// <returns></returns>
public SqlDataReader ReturnDataReader(String sql)
{
Connection.Open();
SqlCommand command = new SqlCommand(sql,Connection);
SqlDataReader dataReader = command.ExecuteReader();

return dataReader;
}

/// <summary>
/// 执行SQL语句，返回记录数
/// </summary>
/// <param name="sql"></param>
/// <returns></returns>
public int ReturnRecordCount(string sql)
{
int recordCount = 0;

Connection.Open();
SqlCommand command = new SqlCommand(sql,Connection);
SqlDataReader dataReader = command.ExecuteReader();

while(dataReader.Read())
{
recordCount++;
}
dataReader.Close();
Connection.Close();

return recordCount;
}

/// <summary>
/// 执行SQL语句
/// </summary>
/// <param name="sql"></param>
/// <returns></returns>
public bool EditDatabase(string sql)
{
bool successState = false;

Connection.Open();
SqlTransaction myTrans = Connection.BeginTransaction();
SqlCommand command = new SqlCommand(sql,Connection,myTrans);
try
{
command.ExecuteNonQuery();
myTrans.Commit();
successState = true;
}
catch
{
myTrans.Rollback();
}
finally
{
Connection.Close();
}

return successState;
}

/// <summary>
/// 关闭数据库联接
/// </summary>
public void Close()
{
Connection.Close();
}

}//end class
}//end namespace