using System; 
Using System. The Data; 
Using System. Text. RegularExpressions; 
Using System. Xml; 
Using System. IO; 
using System.Collections; 
Using System. Data. SQLite; 
Using System. The Configuration;//add the.net reference 
The namespace Utills 
{
///& lt; Summary> 
///class of SQLite operation 
///reference: System. Data. SQLite. DLL [version: 3.6.23.1 (original name: SQlite3. DLL)] 
///& lt;/summary> 
Public class SQLiteHelper 
{
///& lt; Summary> 
///all member functions are static, the constructor defined as private 
///& lt;/summary> 
Private SQLiteHelper () 
{
} 
///& lt; Summary> 
///the connection string 
///& lt;/summary> 
Public static string ConnectionString 
{//"Data Source=Test. Db3; Pooling=true; FailIfMissing=false "; 
The get 
{
////(" SQLiteConnectionString ") under the AppSettings node 
String text=ConfigurationManager. AppSettings [" SQLiteConnectionString "]; 
//string str2=ConfigurationManager. AppSettings [" IsEncrypt "]; 
//if (str2=="true") 
//{
//text=DesEncrypt Decrypt (text); 
//} 
Return the text; 
} 
} 
Private static SQLiteConnection _Conn=null; 
///& lt; Summary> 
///connection object 
///& lt;/summary> 
Public static SQLiteConnection Conn 
{
The get 
{
If (_Conn==null) _Conn=new SQLiteConnection (the ConnectionString); 
Return SQLiteHelper. _Conn; 
} 
The set {SQLiteHelper. _Conn=value; } 
} 


# region CreateCommand (commandText, SQLiteParameter []) 
///& lt; Summary> 
///create a command 
///& lt;/summary> 
///& lt; Param name="connection" & gt; The connection & lt;/param> 
///& lt; Param name="commandText & gt;" The statement & lt;/param> 
///& lt; Param name="commandParameters & gt;" Statement parameters. & lt;/param> 
///& lt; Returns> SQLite Command 
Public static SQLiteCommand CreateCommand (string commandText, params SQLiteParameter [] commandParameters) 
{
SQLiteCommand CMD=new SQLiteCommand (commandText, Conn); 
If (commandParameters. Length & gt; 0) 
{
Foreach (SQLiteParameter parm in commandParameters) 
CMD. The Parameters. The Add (parm); 
} 
Return CMD. 
} 
# endregion 


# region CreateParameter (parameterName parameterType, parameterValue) 
///& lt; Summary> 
///create the parameter 
///& lt;/summary> 
///& lt; Param name="parameterName" & gt; Parameter name & lt;/param> 
///& lt; Param name="parameterType & gt;" The parameter types & lt;/param> 
///& lt; Param name="parameterValue & gt;" The parameter value & lt;/param> 
///& lt; Returns> The parameters of return to create & lt;/returns> 
Public static SQLiteParameter CreateParameter (string parameterName, System. Data. The DbType parameterType, object parameterValue) 
{
SQLiteParameter parameter=new SQLiteParameter (); 
The parameter. The DbType=parameterType; 
The parameter. The ParameterName=ParameterName; 
The parameter Value=https://bbs.csdn.net/topics/parameterValue; 
The return parameter. 
} 
# endregion 

# region ExecuteDataSet (commandText, paramList []) 
///& lt; Summary> 
///
 query dataset///& lt;/summary> 
///& lt; Param name="cn" & gt; Connection. & lt;/param> 
///& lt; Param name="commandText & gt;" Query. & lt;/param> 
///& lt; Param name="paramList & gt;" The object parameter list. & lt;/param> 
///& lt; Returns>  
Public static DataSet ExecuteDataSet (string commandText, params object [] paramList) 
{

SQLiteCommand CMD=Conn. CreateCommand (); 
Cmd.Com mandText=commandText; 
If (paramList!=null) 
{
AttachParameters (CMD, commandText, paramList); 
} 
The DataSet ds=new DataSet (); 
If (Conn. State==ConnectionState. Closed) 
Conn. The Open (); 
SQLiteDataAdapter da=new SQLiteDataAdapter (CMD); 
Da. The Fill (ds); 
Da. The Dispose (); 
CMD. The Dispose (); 
Conn. Close (); 
Return the ds; 
} 
# endregion 

# region ExecuteDataSet (SQLiteCommand) 
///& lt; Summary> 
///
 query dataset///& lt;/summary> 
///& lt; Param name="CMD" & gt; SQLiteCommand object & lt;/param> 
///& lt; Returns> Return data set & lt;/returns> 
Public static DataSet ExecuteDataSet SQLiteCommand (CMD) 
{
If (CMD) Connection. The State==ConnectionState. Closed) 
CMD. Connection. The Open (); 
The DataSet ds=new DataSet (); 
SQLiteDataAdapter da=new SQLiteDataAdapter (CMD); 
Da. The Fill (ds); 
Da. The Dispose (); 
CMD. Connection. The Close (); 
CMD. The Dispose (); 
Return the ds; 
} 
# endregion 

# region ExecuteDataSet (SQLiteTransaction commandText, params SQLiteParameter []) 
///& lt; Summary> 
///
 query dataset///& lt;/summary> 
///& lt; Param name="transaction" & gt; SQLiteTransaction object. & lt;/param> 
///& lt; Param name="commandText & gt;" Query. & lt;/param> 
///& lt; Param name="commandParameters & gt;" The parameter list of commands. & lt;/param> 
///& lt; Returns> DataSet 
///& lt; Remarks> Must be performed manually close the connection transaction. Connection. Close 
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