using System;
namespace com.joybase.DB
{
/// <summary>
/// 數(shù)據(jù)庫操作類，通過這一個類的對外接口，可以獲得以下特性：
/// 1.不必區(qū)分?jǐn)?shù)據(jù)庫類型，而去考慮是使用System.Data.SqlClient實現(xiàn)，或者使用System.Data.OleDB來實現(xiàn);
/// 2.可以將SQL語句進(jìn)行模式化，比如輸入“select * from tablename where username=? order by ? desc"，然后再用建模語句將該語句保持完整;
/// 3.數(shù)據(jù)庫連接實現(xiàn)Connection Pool（該特性是建立在ADO.NET的基礎(chǔ)上的）
/// 4.支持SQL語句的DataReader輸出、無輸出或者DataSet輸出;
/// 5.支持ADO.NET事務(wù)級處理;
/// 6.支持存儲過程的輸入及輸出;
/// </summary>
public class Command
{
//最終的SQL語句;
private System.Text.StringBuilder m_SQL;
//中間過程的SQL語句數(shù)組
private string[] m_SQLArr;
//替代字符串的數(shù)組;
private string[] m_ReplaceText;
//替代字符串的個數(shù);
private int m_Count;
//連接類型;
private System.Data.CommandType m_CommandType;
//在配置文件中用來配置數(shù)據(jù)庫連接字符串的標(biāo)簽;
private string m_ConnstringSetName;
/// <summary>
/// 構(gòu)造方法
/// </summary>
/// <param name="p_sql">模式SQL語句</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>
/// 在配置文件中用來配置數(shù)據(jù)庫連接字符串的標(biāo)簽，如果不設(shè)置，則將采用“DataBase.ConnectionString”作為連接字符串使用
/// </summary>
public string ConnStringSetName
{
set
{
this.m_ConnstringSetName=value;
}
}
/// <summary>
/// 所執(zhí)行命令的類型，即是存儲過程還是普通SQL語句;
/// </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>
/// 以指定的整數(shù)類型，替代在p_location位置上的"?"
/// </summary>
/// <param name="p_location">位置索引</param>
/// <param name="p_InInt">欲替代的整數(shù)</param>
public void setInt(int p_location,int p_InInt)
{
m_ReplaceText[p_location-1]=p_InInt.ToString();
}
/// <summary>
/// 以指定的長整數(shù)類型，替代在p_location位置上的"?"
/// </summary>
/// <param name="p_location">位置索引</param>
/// <param name="p_InLong">欲替代的長整數(shù)</param>
public void setLong(int p_location,int p_InLong)
{
m_ReplaceText[p_location-1]=p_InLong.ToString();
}
/// <summary>
/// 以指定的時間，替代在p_location位置上的"?"
/// </summary>
/// <param name="p_location">位置索引</param>
/// <param name="p_InDateTime">欲替代的時間</param>
public void setDateTime(int p_location,System.DateTime p_InDateTime)
{
m_ReplaceText[p_location-1]=p_InDateTime.ToString();
}
/// <summary>
/// 以系統(tǒng)時間替代在p_location位置的"?"
/// </summary>
/// <param name="p_location">位置索引</param>
/// <param name="p_OnLyDate">如果為True，則僅替代到日期，如果為False，則替代到時間</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>
/// 執(zhí)行命令并且返回System.Data.IDataReader結(jié)果的結(jié)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>
/// 無結(jié)果執(zhí)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");
}

}
}
}