using System;
namespace com.joybase.DB
{
/// <summary>
/// 数据库操作类，通过这一个类的对外接口，可以获得以下特性：
/// 1.不必区分数据库类型，而去考虑是使用System.Data.SqlClient实现，或者使用System.Data.OleDB来实现;
/// 2.可以将SQL语句进行模式化，比如输入“select * from tablename where username=? order by ? desc"，然后再用建模语句将该语句保持完整;
/// 3.数据库连接实现Connection Pool（该特性是建立在ADO.NET的基础上的）
/// 4.支持SQL语句的DataReader输出、无输出或者DataSet输出;
/// 5.支持ADO.NET事务级处理;
/// 6.支持存储过程的输入及输出;
/// </summary>
public class Command
{
//最终的SQL语句;
private System.Text.StringBuilder m_SQL;
//中间过程的SQL语句数组
private string[] m_SQLArr;
//替代字符串的数组;
private string[] m_ReplaceText;
//替代字符串的个数;
private int m_Count;
//连接类型;
private System.Data.CommandType m_CommandType;
//在配置文件中用来配置数据库连接字符串的标签;
private string m_ConnstringSetName;
/// <summary>
/// 构造方法
/// </summary>
/// <param name="p_sql">模式SQL语句</param>
public Command(string p_sql)
{
if(p_sql==null) throw new Exception("Error Value");
if(p_sql.Trim()=="") throw new Exception("Error Value");
this.m_SQL=new System.Text.StringBuilder();
m_SQLArr=p_sql.Split('?');
m_Count=m_SQLArr.Length;
m_ReplaceText=new string[m_Count-1];
m_ConnstringSetName="";
this.m_CommandType=System.Data.CommandType.Text;
}
/// <summary>
/// 在配置文件中用来配置数据库连接字符串的标签，如果不设置，则将采用“DataBase.ConnectionString”作为连接字符串使用
/// </summary>
public string ConnStringSetName
{
set
{
this.m_ConnstringSetName=value;
}
}
/// <summary>
/// 所执行命令的类型，即是存储过程还是普通SQL语句;
/// </summary>
public System.Data.CommandType CommandType
{
set
{
this.m_CommandType=value;
}
}
/// <summary>
/// 以指定的字符串替代在p_loaction位置上的“?”;
/// </summary>
/// <param name="p_location">位置索引</param>
/// <param name="p_InString">欲替代的字符串</param>
public void setString(int p_location,string p_InString)
{
if(p_InString==null) throw new Exception("Error Value");
if(p_InString.Trim()==null) throw new Exception("Error Value");
m_ReplaceText[p_location-1]="'"+p_InString.Trim()+"'";
}
/// <summary>
/// 以指定的整数类型，替代在p_location位置上的"?"
/// </summary>
/// <param name="p_location">位置索引</param>
/// <param name="p_InInt">欲替代的整数</param>
public void setInt(int p_location,int p_InInt)
{
m_ReplaceText[p_location-1]=p_InInt.ToString();
}
/// <summary>
/// 以指定的长整数类型，替代在p_location位置上的"?"
/// </summary>
/// <param name="p_location">位置索引</param>
/// <param name="p_InLong">欲替代的长整数</param>
public void setLong(int p_location,int p_InLong)
{
m_ReplaceText[p_location-1]=p_InLong.ToString();
}
/// <summary>
/// 以指定的时间，替代在p_location位置上的"?"
/// </summary>
/// <param name="p_location">位置索引</param>
/// <param name="p_InDateTime">欲替代的时间</param>
public void setDateTime(int p_location,System.DateTime p_InDateTime)
{
m_ReplaceText[p_location-1]=p_InDateTime.ToString();
}
/// <summary>
/// 以系统时间替代在p_location位置的"?"
/// </summary>
/// <param name="p_location">位置索引</param>
/// <param name="p_OnLyDate">如果为True，则仅替代到日期，如果为False，则替代到时间</param>
public void setDateTime(int p_location,bool p_OnlyDate)
{
if(p_OnlyDate)
m_ReplaceText[p_location-1]=System.DateTime.Now.Date.ToString();
else
m_ReplaceText[p_location-1]=System.DateTime.Now.ToString();
}
private string JoinSQLString()
{
for(int i=0;i<m_Count;i++)
{
if(i!=0) this.m_SQL.Append(m_ReplaceText[i-1]);
this.m_SQL.Append(m_SQLArr[i]);
}
return this.m_SQL.ToString();
}
/// <summary>
/// 执行命令并且返回System.Data.IDataReader结果的结果集
/// </summary>
/// <returns></returns>
public System.Data.IDataReader Result()
{
System.Data.IDataReader result=null;
try
{
System.Data.IDbCommand command=Provider.getConn(m_ConnstringSetName).CreateCommand();
command.CommandText=this.JoinSQLString();
command.CommandType=this.m_CommandType;
command.Connection.Close();
command.Connection.Open();
command.Prepare();
//if(Provider.getConn(m_ConnstringSetName).State==System.Data.ConnectionState.Closed)
//Provider.getConn(m_ConnstringSetName).Open();
result=command.ExecuteReader();
//command.Connection.Close();
//Provider.getConn().Close();
}
catch
{
throw new Exception("error at execute db command");
}
return result;
}
/// <summary>
/// 无结果执行命令
/// </summary>
public void ExecuteNoResult()
{
try
{
System.Data.IDbCommand command=Provider.getConn(m_ConnstringSetName).CreateCommand();
command.CommandText=this.JoinSQLString();
command.CommandType=this.m_CommandType;
command.Connection.Close();
command.Connection.Open();
//if(Provider.getConn(m_ConnstringSetName).State==System.Data.ConnectionState.Closed)
//Provider.getConn(m_ConnstringSetName).Open();
command.ExecuteNonQuery();
}
catch
{
throw new Exception("Error at execute DB Command");
}
}
}
}
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