Google Gears SQL Lite数据库和C＃

Question

Google Gears使用SQL Lite作为数据存储。有没有人用C＃成功连接到Google Gears SQL Lite数据库？

感谢

Answer 1

看看我最喜欢的SQLite ADO.NET Wrapper，我个人在很多项目中使用。我猜想，Google Gears正在使用默认的SQLite数据库，并在代码中进行了一些修改，以防止ATTACH和#PRAGMA的使用。但数据格式应该是相同的，所以你应该能够使用这个包装来访问它。

最好的问候， 马丁

Answer 2

//嗨，试试这个：

//Courtesy of http://www.codoxide.com/post/My-Favorite-Database-Wrapper-for-C.aspx 
using System; 
using System.Collections.Generic; 
using System.Text; 
using System.Data; 
using System.Data.Common; 

namespace GenApp.Core.Providers.nsDb 
{ 
    //comm --/<summary> 
    //comm --/Abstract base class for encapsulating provider independant database interactin logic. 
    //comm --/</summary> 
    //comm --/<typeparam name="CONNECTION_TYPE"><see cref="DbConnection"/> derived Connection type.</typeparam> 
    //comm --/<typeparam name="COMMAND_TYPE"><see cref="DbCommand"/> derived Command type.</typeparam> 
    //comm --/<typeparam name="ADAPTER_TYPE"><see cref="DbDataAdapater"/> derived Data Adapter type.</typeparam> 
    public abstract 
     class AbstractDatabase<CONNECTION_TYPE, COMMAND_TYPE, ADAPTER_TYPE> : IDisposable 
     where CONNECTION_TYPE : DbConnection, new() 
     where COMMAND_TYPE : DbCommand 
     where ADAPTER_TYPE : DbDataAdapter, new() 
    { 
     #region : Connection : 

     //comm --/<summary>Gets the Connection object associated with the current instance.</summary> 
     public DbConnection Connection 
     { 
      get 
      { 
       if (internal_currentConnection == null) 
       { 
        internal_currentConnection = new CONNECTION_TYPE(); 
             // - Enable to measure the connection timeGenApp.Core.Providers.nsDbMeta.DbDebugger.WriteIf (ref userObj , "GetConnectionString START"); 
        internal_currentConnection.ConnectionString = GetConnectionString(); 
             // - Enable to measure the connection timeGenApp.Core.Providers.nsDbMeta.DbDebugger.WriteIf (ref userObj , "GetConnectionString END"); 
       } 
       return internal_currentConnection; 
      } 
     } 
     private DbConnection internal_currentConnection; 

     //comm --/<summary>When overridden in derived classes returns the connection string for the database.</summary> 
     //comm --/<returns>The connection string for the database.</returns> 
     protected abstract string GetConnectionString(); 

     #endregion 

     #region : Commands : 

     //comm --/<summary>Gets a DbCommand object with the specified <see cref="DbCommand.CommandText"/>.</summary> 
     //comm --/<param name="sqlString">The SQL string.</param> 
     //comm --/<returns>A DbCommand object with the specified <see cref="DbCommand.CommandText"/>.</returns> 
     public DbCommand GetSqlStringCommand(string sqlString) 
     { 
      if (this.Connection.State != ConnectionState.Open) 
       this.Connection.Open(); 

      DbCommand cmd = this.Connection.CreateCommand(); 
      cmd.CommandType = CommandType.Text; 
      cmd.CommandText = sqlString; 
      return cmd; 
     } 

     //comm --/<summary>Gets a DbCommand object with the specified <see cref="DbCommand.CommandText"/>.</summary> 
     //comm --/<param name="sqlStringFormat">The SQL string format.</param> 
     //comm --/<param name="args">The format arguments.</param> 
     //comm --/<returns>A DbCommand object with the specified <see cref="DbCommand.CommandText"/>.</returns> 
     public DbCommand GetSqlStringCommand(string sqlStringFormat, params object[] args) 
     { 
      return GetSqlStringCommand(string.Format(sqlStringFormat, args)); 
     } 

     //comm --/<summary>Gets a DbCommand object for the specified Stored Procedure.</summary> 
     //comm --/<param name="storedProcName">The name of the stored procedure.</param> 
     //comm --/<returns>A DbCommand object for the specified Stored Procedure.</returns> 
     public DbCommand GetStoredProcedureCommand(string storedProcName) 
     { 
      if (this.Connection.State != ConnectionState.Open) 
       this.Connection.Open(); 

      DbCommand cmd = this.Connection.CreateCommand(); 
      cmd.CommandType = CommandType.StoredProcedure; 
      cmd.CommandText = storedProcName; 
      return cmd; 
     } 

     #region : Parameters : 

     //comm --/<summary>Adds an input parameter to the given <see cref="DbCommand"/>.</summary> 
     //comm --/<param name="cmd">The command object the parameter should be added to.</param> 
     //comm --/<param name="paramName">The identifier of the parameter.</param> 
     //comm --/<param name="paramType">The type of the parameter.</param> 
     //comm --/<param name="value">The value of the parameter.</param> 
     //comm --/<returns>The <see cref="DbParameter"/> that was created.</returns> 
     public DbParameter AddInParam(DbCommand cmd, string paramName, DbType paramType, object value) 
     { 
      DbParameter param  = cmd.CreateParameter(); 
      param.DbType   = paramType; 
      param.ParameterName  = paramName; 
      param.Value    = value; 
      param.Direction   = ParameterDirection.Input; 
      cmd.Parameters.Add(param); 
      return param; 
       } //eof method AddInParam 

     //comm --/<summary>Adds an input parameter to the given <see cref="DbCommand"/>.</summary> 
     //comm --/<param name="cmd">The command object the parameter should be added to.</param> 
     //comm --/<param name="paramName">The identifier of the parameter.</param> 
     //comm --/<param name="paramType">The type of the parameter.</param> 
     //comm --/<param name="size">The maximum size in bytes, of the data table column to be affected.</param> 
     //comm --/<param name="value">The value of the parameter.</param> 
     //comm --/<returns>The <see cref="DbParameter"/> that was created.</returns> 
     public DbParameter AddInParam(DbCommand cmd, string paramName, DbType paramType, int size, object value) 
     { 
      DbParameter param  = cmd.CreateParameter(); 
      param.DbType   = paramType; 
      param.ParameterName  = paramName; 
      param.Size    = size; 
      param.Value    = value; 
      param.Direction   = ParameterDirection.Input; 
      //debugGenApp.Core.Providers.nsDbMeta.DbDebugger.WriteIf (ref userObj , "Adding IN param " + value.ToString ()); 
      cmd.Parameters.Add(param); 
      return param; 
     } 

     public DbParameter AddInOutParam (DbCommand cmd, string paramName, DbType paramType, int size, object value) 
      { 
      DbParameter param = cmd.CreateParameter (); 
      param.DbType = paramType; 
      param.ParameterName = paramName; 
      param.Size = size; 
      param.Value = value; 
      param.Direction = ParameterDirection.Output; 
      cmd.Parameters.Add (param); 
      //debug if needed here 
      return param; 
      } 


     public DbParameter AddInOutParam (DbCommand cmd, string paramName, DbType paramType, object value) 
      { 
      DbParameter param = cmd.CreateParameter (); 
      param.DbType = paramType; 
      param.ParameterName = paramName; 
      param.Value = value; 
      param.Direction = ParameterDirection.Output; 
      cmd.Parameters.Add (param); 
      return param; 
      } 

     #endregion 

     #region : Executes : 

     //comm --/<summary>Executes the specified command against the current connection.</summary> 
     //comm --/<param name="cmd">The command to be executed.</param> 
     //comm --/<returns>Result returned by the database engine.</returns> 
     public int ExecuteNonQuery(DbCommand cmd) 
     { 
      if (this.Connection.State != ConnectionState.Open) 
       this.Connection.Open(); 

      return cmd.ExecuteNonQuery(); 
     } 

     //comm --/<summary>Executes the specified command against the current connection.</summary> 
     //comm --/<param name="cmd">The command to be executed.</param> 
     //comm --/<param name="txn">The database transaction inside which the command should be executed.</param> 
     //comm --/<returns>Result returned by the database engine.</returns> 
     public int ExecuteNonQuery(DbCommand cmd, DbTransaction txn) 
     { 
      if (this.Connection.State != ConnectionState.Open) 
       this.Connection.Open(); 

      cmd.Transaction = txn; 
      return cmd.ExecuteNonQuery(); 
     } 

     //comm --/<summary>Executes the specified command against the current connection.</summary> 
     //comm --/<param name="cmd">The command to be executed.</param> 
     //comm --/<returns>Result returned by the database engine.</returns> 
     public DbDataReader ExecuteReader(DbCommand cmd) 
     { 
      if (this.Connection.State != ConnectionState.Open) 
       this.Connection.Open(); 

      return cmd.ExecuteReader(); 
     } 

     //comm --/<summary>Executes the specified command against the current connection.</summary> 
     //comm --/<param name="cmd">The command to be executed.</param> 
     //comm --/<param name="behavior">One of the <see cref="System.Data.CommandBehavior"/> values.</param> 
     //comm --/<returns>Result returned by the database engine.</returns> 
     public DbDataReader ExecuteReader(DbCommand cmd , CommandBehavior behavior) 
     { 
      if (this.Connection.State != ConnectionState.Open) 
       this.Connection.Open(); 

      return cmd.ExecuteReader(behavior); 
     } 

     //comm --/<summary>Executes the specified command against the current connection.</summary> 
     //comm --/<param name="cmd">The command to be executed.</param> 
     //comm --/<returns>Result returned by the database engine.</returns> 
     public T ExecuteScalar<T>(DbCommand cmd, T defaultValue) 
     { 
      if (this.Connection.State != ConnectionState.Open) 
       this.Connection.Open(); 

      object retVal = cmd.ExecuteScalar(); 
      if (null == retVal || DBNull.Value == retVal) 
       return defaultValue; 
      else 
       return (T)retVal; 
     } 

     //comm --/<summary>Executes the specified command against the current connection.</summary> 
     //comm --/<param name="cmd">The command to be executed.</param> 
     //comm --/<returns>Result returned by the database engine.</returns> 
     public DataSet ExecuteDataSet(DbCommand cmd) 
     { 
      ADAPTER_TYPE adapter = new ADAPTER_TYPE(); 
      adapter.SelectCommand = (COMMAND_TYPE)cmd; 


      DataSet retVal = new DataSet(); 
      adapter.Fill(retVal); 
      return retVal; 
     } 

     ////comm --/<summary>Executes the specified command against the current connection.</summary> 
     ////comm --/<param name="cmd">The command to be executed.</param> 
     ////comm --/<returns>Result returned by the database engine.</returns> 
     //public DataSet ExecuteDataSet(DbCommand cmd) 
     //{ 
     // ADAPTER_TYPE adapter = new ADAPTER_TYPE(); 
     // adapter.SelectCommand = (COMMAND_TYPE)cmd; 
     // //cmd.CommandTimeout = 3600 
     // DataSet retVal = new DataSet(); 
     // adapter.Fill(retVal); 
     // return retVal; 
     //} 

     #endregion 

     #endregion 

     //comm --/<summary>Begins a transaction.</summary> 
     //comm --/<returns>Created transaction.</returns> 
     public DbTransaction BeginTransaction() 
     { 
      if (this.Connection.State != ConnectionState.Open) 
       this.Connection.Open(); 
      return Connection.BeginTransaction(); 
     } 

     #region : Construction/Destruction : 

     //comm --/<summary>Disposes the resources associated with the current database connection.</summary> 
     ~AbstractDatabase() 
     { 
      Dispose(); 
     } 

     #region IDisposable Members 

     //comm --/<summary>Disposes the resources associated with the current database connection.</summary> 
     public void Dispose() 
     { 
      if (null != internal_currentConnection) 
      { 
       internal_currentConnection.Dispose(); 
       internal_currentConnection = null; 
      } 
     } 

     #endregion 

     #endregion 

    } //eof public abstract class AbstractDatabase 
} //eof namespace Providers.nsDb 


using System; 
using System.Collections.Generic; 
using System.Text; 
using System.Data.SqlClient; 


namespace GenApp.Core.Providers.nsDb 
{ 
    public class Database : AbstractDatabase<SqlConnection, SqlCommand, SqlDataAdapter> 
    { 




        private string _ConnectionString; 
        public string ConnectionString 
        { 
         get { return _ConnectionString; } 
         set { _ConnectionString = value; } 
        } //eof property FieldName 

        public Database (string connectionStr) 
        { 
      //debugGenApp.Core.Providers.nsDbMeta.DbDebugger.WriteIf(ref userObj , " CHECK --- nsDb.Database using the following connection string " + connectionStr); 
         this.ConnectionString = connectionStr; 
        } //eof constructor 


      protected override string GetConnectionString () 
      { 

       //GenApp.Core.Providers.nsDbMeta.DbDebugger.WriteIf (ref userObj , "In GetConnectionString the ConnectionString is " + this.ConnectionString); 
       //GenApp.Core.Providers.nsDbMeta.DbDebugger.WriteIf (ref userObj , "The comming fromURL IS " + commingFromURL); 
       return this._ConnectionString; 
      } //eof protected override string GetConnectionString() 

    } //eof class 
} //eof namespace Providers.nsDb 

Answer 3

//所以会使用这样的： //

公共BOOL RunProcGetDs（REF string信息，字符串则domainName ，string procedureName，ref DataSet ds） {

 #region Action 
     try 
     { 
      using (Database db = new Database (_ConnectionString)) 
      { 
       DbCommand cmd = db.GetStoredProcedureCommand (procedureName); 
       db.AddInParam (cmd, "@domain_user", DbType.String, (object)domainName); 

       GenApp.Core.Providers.nsDbMeta.DbDebugger.WriteIf (ref userObj , "METHOD START --- MetaDbControl.cs RunProcGetDs + \n"); 


       ds = db.ExecuteDataSet (cmd); 
       Utils.Debugger.DebugDataSet("from RunProcGetDs ", ref ds); 

       //debug msg = "Select the values for your reports"; 
       return true; 
      } //eof using 
     } //eof try 
     #endregion Action 


     #region CatchExceptionsAdv4 
     catch (NullReferenceException nre) 
     { 
      System.Diagnostics.StackTrace st = new System.Diagnostics.StackTrace(); 
      string methodName = st.GetFrame (1).GetMethod().Name; 
      string className = st.GetFrame (1).GetFileName(); 
      int lineNumber = st.GetFrame (1).GetFileLineNumber(); 

      string encryptedErrorCode = String.Empty; 
      encryptedErrorCode += "className - " + className + " methodName "; 
      encryptedErrorCode += methodName + " lineNumber " + lineNumber.ToString(); 
      encryptedErrorCode += userObj.DomainName; 

      if (System.Convert.ToInt16 (BL.Conf.Instance.Vars["EncryptErrorMessages"]) == 1) 
       encryptedErrorCode = Utils.DataEncryption.EncryptString (encryptedErrorCode, userObj.DomainName); 


      userObj.Mc.Msg = "An error in the application occurred. Report the following error code " + encryptedErrorCode; 
      userObj.Mc.ClassName += className + " ; " ; 
      userObj.Mc.MethodName += methodName + " ; " ; 
      userObj.Mc.DebugMsg += nre.Message; 

      if (DbDebugger.DebugAppError (ref userObj) == false) 
      { 
       userObj.Mc.Msg = "Failed to debug application error at " + methodName; 

GenApp.Core.Providers.nsDbMeta.DbDebugger.WriteIf（userObj.Mc.Msg）; } return false; } // EOF赶上

 catch (System.InvalidOperationException ioe) //comm -- occurs when no result set was found !!! 
     { 
      System.Diagnostics.StackTrace st = new System.Diagnostics.StackTrace(); 
      string methodName = st.GetFrame (1).GetMethod().Name; 
      string className = st.GetFrame (1).GetFileName(); 
      int lineNumber = st.GetFrame (1).GetFileLineNumber(); 

      string encryptedErrorCode = String.Empty; 
      encryptedErrorCode += "className - " + className + " methodName "; 
      encryptedErrorCode += methodName + " lineNumber " + lineNumber.ToString(); 
      encryptedErrorCode += userObj.DomainName; 

      if (System.Convert.ToInt16 (BL.Conf.Instance.Vars["EncryptErrorMessages"]) == 1) 
       encryptedErrorCode = Utils.DataEncryption.EncryptString (encryptedErrorCode, userObj.DomainName); 


      userObj.Mc.Msg = "An error in the application occurred. Report the following error code " + encryptedErrorCode; 
      userObj.Mc.ClassName += className + " ; " ; 
      userObj.Mc.MethodName += methodName + " ; " ; 
      userObj.Mc.DebugMsg += ioe.Message; 

      if (DbDebugger.DebugAppError (ref userObj) == false) 
      { 
       userObj.Mc.Msg = "Failed to debug application error at " + methodName; 

GenApp.Core.Providers.nsDbMeta.DbDebugger.WriteIf（userObj.Mc.Msg）; } return false; } // EOF赶上（System.InvalidOperationException）

 catch (System.IndexOutOfRangeException ioore) //comm -- occurs when no result set was found !!! 
     { 
      System.Diagnostics.StackTrace st = new System.Diagnostics.StackTrace(); 
      string methodName = st.GetFrame (1).GetMethod().Name; 
      string className = st.GetFrame (1).GetFileName(); 
      int lineNumber = st.GetFrame (1).GetFileLineNumber(); 

      string encryptedErrorCode = String.Empty; 
      encryptedErrorCode += "className - " + className + " methodName "; 
      encryptedErrorCode += methodName + " lineNumber " + lineNumber.ToString(); 
      encryptedErrorCode += userObj.DomainName; 

      if (System.Convert.ToInt16 (BL.Conf.Instance.Vars["EncryptErrorMessages"]) == 1) 
       encryptedErrorCode = Utils.DataEncryption.EncryptString (encryptedErrorCode, userObj.DomainName); 


      userObj.Mc.Msg = "An error in the application occurred. Report the following error code " + encryptedErrorCode; 
      userObj.Mc.ClassName += className + " ; " ; 
      userObj.Mc.MethodName += methodName + " ; " ; 
      userObj.Mc.DebugMsg += ioore.Message; 

      if (DbDebugger.DebugAppError (ref userObj) == false) 
      { 
       userObj.Mc.Msg = "Failed to debug application error at " + methodName; 

GenApp.Core.Providers.nsDbMeta.DbDebugger.WriteIf（userObj.Mc.Msg）; } return false; } // EOF赶上（System.IndexOutOfRangeException）

 catch (System.Data.SqlClient.SqlException sqle) 
     { 
      System.Diagnostics.StackTrace st = new System.Diagnostics.StackTrace(); 
      string methodName = st.GetFrame (1).GetMethod().Name; 
      string className = st.GetFrame (1).GetFileName(); 
      int lineNumber = st.GetFrame (1).GetFileLineNumber(); 

      string encryptedErrorCode = String.Empty; 
      encryptedErrorCode += "className - " + className + " methodName "; 
      encryptedErrorCode += methodName + " lineNumber " + lineNumber.ToString(); 
      encryptedErrorCode += userObj.DomainName; 

      if (System.Convert.ToInt16 (BL.Conf.Instance.Vars["EncryptErrorMessages"]) == 1) 
       encryptedErrorCode = Utils.DataEncryption.EncryptString (encryptedErrorCode, userObj.DomainName); 


      userObj.Mc.Msg = "An error in the application occurred. Report the following error code " + encryptedErrorCode; 
      userObj.Mc.ClassName += className + " ; " ; 
      userObj.Mc.MethodName += methodName + " ; " ; 
      userObj.Mc.DebugMsg += sqle.Message; 

      if (DbDebugger.DebugAppError (ref userObj) == false) 
      { 
       userObj.Mc.Msg = "Failed to debug application error at " + methodName; 

GenApp.Core.Providers.nsDbMeta.DbDebugger.WriteIf（userObj.Mc.Msg）; } return false; } // EOF赶上

 catch (System.FormatException fe) 
     { 
      System.Diagnostics.StackTrace st = new System.Diagnostics.StackTrace(); 
      string methodName = st.GetFrame (1).GetMethod().Name; 
      string className = st.GetFrame (1).GetFileName(); 
      int lineNumber = st.GetFrame (1).GetFileLineNumber(); 

      string encryptedErrorCode = String.Empty; 
      encryptedErrorCode += "className - " + className + " methodName "; 
      encryptedErrorCode += methodName + " lineNumber " + lineNumber.ToString(); 
      encryptedErrorCode += userObj.DomainName; 

      if (System.Convert.ToInt16 (BL.Conf.Instance.Vars["EncryptErrorMessages"]) == 1) 
       encryptedErrorCode = Utils.DataEncryption.EncryptString (encryptedErrorCode, userObj.DomainName); 


      userObj.Mc.Msg = "An error in the application occurred. Report the following error code " + encryptedErrorCode; 
      userObj.Mc.ClassName += className + " ; " ; 
      userObj.Mc.MethodName += methodName + " ; " ; 
      userObj.Mc.DebugMsg += fe.Message; 

      if (DbDebugger.DebugAppError (ref userObj) == false) 
      { 
       userObj.Mc.Msg = "Failed to debug application error at " + methodName; 

GenApp.Core.Providers.nsDbMeta.DbDebugger.WriteIf（userObj.Mc.Msg）; } return false; } // EOF赶上

 catch (Exception ex) 
     { 
      System.Diagnostics.StackTrace st = new System.Diagnostics.StackTrace(); 
      string methodName = st.GetFrame (1).GetMethod().Name; 
      string className = st.GetFrame (1).GetFileName(); 
      int lineNumber = st.GetFrame (1).GetFileLineNumber(); 

      string encryptedErrorCode = String.Empty; 
      encryptedErrorCode += "className - " + className + " methodName "; 
      encryptedErrorCode += methodName + " lineNumber " + lineNumber.ToString(); 
      encryptedErrorCode += userObj.DomainName; 

      if (System.Convert.ToInt16 (BL.Conf.Instance.Vars["EncryptErrorMessages"]) == 1) 
       encryptedErrorCode = Utils.DataEncryption.EncryptString (encryptedErrorCode, userObj.DomainName); 


      userObj.Mc.Msg = "An error in the application occurred. Report the following error code " + encryptedErrorCode; 
      userObj.Mc.ClassName += className + " ; " ; 
      userObj.Mc.MethodName += methodName + " ; " ; 
      userObj.Mc.DebugMsg += ex.Message; 

      if (DbDebugger.DebugAppError (ref userObj) == false) 
      { 
       userObj.Mc.Msg = "Failed to debug application error at " + methodName; 

GenApp.Core.Providers.nsDbMeta.DbDebugger.WriteIf（userObj.Mc.Msg）; } return false; } // EOF赶 #endregion CatchExceptionsAdv4

} //eof method