sqlitedatareader.cs

sqlite 3.3.8 支持加密的版本

    /// <param name="i">The index of the column to retrieve</param>
    /// <returns>string</returns>
    public override string GetDataTypeName(int i)
    {
      CheckClosed();
      SQLiteType typ = GetSQLiteType(i);

      if (typ.Type == DbType.Object) return SQLiteConvert.SQLiteTypeToType(typ).Name;

      return _activeStatement._sql.ColumnType(_activeStatement, i, out typ.Affinity);
    }

    /// <summary>
    /// Retrieve the column as a date/time value
    /// </summary>
    /// <param name="i">The index of the column to retrieve</param>
    /// <returns>DateTime</returns>
    public override DateTime GetDateTime(int i)
    {
      VerifyType(i, DbType.DateTime);
      return _activeStatement._sql.GetDateTime(_activeStatement, i);
    }

    /// <summary>
    /// Retrieve the column as a decimal value
    /// </summary>
    /// <param name="i">The index of the column to retrieve</param>
    /// <returns>decimal</returns>
    public override decimal GetDecimal(int i)
    {
      VerifyType(i, DbType.Decimal);
      return Convert.ToDecimal(_activeStatement._sql.GetDouble(_activeStatement, i));
    }

    /// <summary>
    /// Returns the column as a double
    /// </summary>
    /// <param name="i">The index of the column to retrieve</param>
    /// <returns>double</returns>
    public override double GetDouble(int i)
    {
      VerifyType(i, DbType.Double);
      return _activeStatement._sql.GetDouble(_activeStatement, i);
    }

    /// <summary>
    /// Returns the .NET type of a given column
    /// </summary>
    /// <param name="i">The index of the column to retrieve</param>
    /// <returns>Type</returns>
    public override Type GetFieldType(int i)
    {
      CheckClosed();
      return SQLiteConvert.SQLiteTypeToType(GetSQLiteType(i));
    }

    /// <summary>
    /// Returns a column as a float value
    /// </summary>
    /// <param name="i">The index of the column to retrieve</param>
    /// <returns>float</returns>
    public override float GetFloat(int i)
    {
      VerifyType(i, DbType.Single);
      return Convert.ToSingle(_activeStatement._sql.GetDouble(_activeStatement, i));
    }

    /// <summary>
    /// Returns the column as a Guid
    /// </summary>
    /// <param name="i">The index of the column to retrieve</param>
    /// <returns>Guid</returns>
    public override Guid GetGuid(int i)
    {
      TypeAffinity affinity = VerifyType(i, DbType.Guid);
      if (affinity == TypeAffinity.Blob)
      {
        byte[] buffer = new byte[16];
        _activeStatement._sql.GetBytes(_activeStatement, i, 0, buffer, 0, 16);
        return new Guid(buffer);
      }
      else
        return new Guid(_activeStatement._sql.GetText(_activeStatement, i));
    }

    /// <summary>
    /// Returns the column as a short
    /// </summary>
    /// <param name="i">The index of the column to retrieve</param>
    /// <returns>Int16</returns>
    public override Int16 GetInt16(int i)
    {
      VerifyType(i, DbType.Int16);
      return Convert.ToInt16(_activeStatement._sql.GetInt32(_activeStatement, i));
    }

    /// <summary>
    /// Retrieves the column as an int
    /// </summary>
    /// <param name="i">The index of the column to retrieve</param>
    /// <returns>Int32</returns>
    public override Int32 GetInt32(int i)
    {
      VerifyType(i, DbType.Int32);
      return _activeStatement._sql.GetInt32(_activeStatement, i);
    }

    /// <summary>
    /// Retrieves the column as a long
    /// </summary>
    /// <param name="i">The index of the column to retrieve</param>
    /// <returns>Int64</returns>
    public override Int64 GetInt64(int i)
    {
      VerifyType(i, DbType.Int64);
      return _activeStatement._sql.GetInt64(_activeStatement, i);
    }

    /// <summary>
    /// Retrieves the name of the column
    /// </summary>
    /// <param name="i">The index of the column to retrieve</param>
    /// <returns>string</returns>
    public override string GetName(int i)
    {
      CheckClosed();
      return _activeStatement._sql.ColumnName(_activeStatement, i);
    }

    /// <summary>
    /// Retrieves the i of a column, given its name
    /// </summary>
    /// <param name="name">The name of the column to retrieve</param>
    /// <returns>The int i of the column</returns>
    public override int GetOrdinal(string name)
    {
      CheckClosed();
      return _activeStatement._sql.ColumnIndex(_activeStatement, name);
    }

    /// <summary>
    /// Schema information in SQLite is difficult to map into .NET conventions, so a lot of work must be done
    /// to gather the necessary information so it can be represented in an ADO.NET manner.
    /// </summary>
    /// <returns>Returns a DataTable containing the schema information for the active SELECT statement being processed.</returns>
    public override DataTable GetSchemaTable()
    {
      return GetSchemaTable(true, true);
    }

    internal DataTable GetSchemaTable(bool wantUniqueInfo, bool wantDefaultValue)
    {
      CheckClosed();

      DataTable tbl = new DataTable("SchemaTable");
      DataTable tblIndexes = null;
      DataTable tblIndexColumns;
      DataRow row;
      string temp;
      string strCatalog = "";
      string strTable = "";
      string strColumn = "";

      tbl.Locale = CultureInfo.InvariantCulture;
      tbl.Columns.Add(SchemaTableColumn.ColumnName, typeof(String));
      tbl.Columns.Add(SchemaTableColumn.ColumnOrdinal, typeof(int));
      tbl.Columns.Add(SchemaTableColumn.ColumnSize, typeof(int));
      tbl.Columns.Add(SchemaTableColumn.NumericPrecision, typeof(short));
      tbl.Columns.Add(SchemaTableColumn.NumericScale, typeof(short));
      tbl.Columns.Add(SchemaTableColumn.IsUnique, typeof(Boolean));
      tbl.Columns.Add(SchemaTableColumn.IsKey, typeof(Boolean));
      tbl.Columns.Add(SchemaTableOptionalColumn.BaseServerName, typeof(string));
      tbl.Columns.Add(SchemaTableOptionalColumn.BaseCatalogName, typeof(String));
      tbl.Columns.Add(SchemaTableColumn.BaseColumnName, typeof(String));
      tbl.Columns.Add(SchemaTableColumn.BaseSchemaName, typeof(String));
      tbl.Columns.Add(SchemaTableColumn.BaseTableName, typeof(String));
      tbl.Columns.Add(SchemaTableColumn.DataType, typeof(Type));
      tbl.Columns.Add(SchemaTableColumn.AllowDBNull, typeof(Boolean));
      tbl.Columns.Add(SchemaTableColumn.ProviderType, typeof(int));
      tbl.Columns.Add(SchemaTableColumn.IsAliased, typeof(Boolean));
      tbl.Columns.Add(SchemaTableColumn.IsExpression, typeof(Boolean));
      tbl.Columns.Add(SchemaTableOptionalColumn.IsAutoIncrement, typeof(Boolean));
      tbl.Columns.Add(SchemaTableOptionalColumn.IsRowVersion, typeof(Boolean));
      tbl.Columns.Add(SchemaTableOptionalColumn.IsHidden, typeof(Boolean));
      tbl.Columns.Add(SchemaTableColumn.IsLong, typeof(Boolean));
      tbl.Columns.Add(SchemaTableOptionalColumn.IsReadOnly, typeof(Boolean));
      tbl.Columns.Add(SchemaTableOptionalColumn.ProviderSpecificDataType, typeof(Type));
      tbl.Columns.Add(SchemaTableOptionalColumn.DefaultValue, typeof(object));
      tbl.Columns.Add("DataTypeName", typeof(string));

      tbl.BeginLoadData();

      for (int n = 0; n < _fieldCount; n++)
      {
        row = tbl.NewRow();

        // Default settings for the column
        row[SchemaTableColumn.ColumnName] = GetName(n);
        row[SchemaTableColumn.ColumnOrdinal] = n;
        row[SchemaTableColumn.ColumnSize] = SQLiteConvert.DbTypeToColumnSize(GetSQLiteType(n).Type);
        row[SchemaTableColumn.NumericPrecision] = 255;
        row[SchemaTableColumn.NumericScale] = 255;
        row[SchemaTableColumn.ProviderType] = GetSQLiteType(n).Type;
        row[SchemaTableColumn.IsLong] = (GetSQLiteType(n).Type == DbType.Binary);
        row[SchemaTableColumn.AllowDBNull] = true;
        row[SchemaTableOptionalColumn.IsReadOnly] = false;
        row[SchemaTableOptionalColumn.IsRowVersion] = false;
        row[SchemaTableColumn.IsUnique] = false;
        row[SchemaTableColumn.IsKey] = false;
        row[SchemaTableOptionalColumn.IsAutoIncrement] = false;
        row[SchemaTableOptionalColumn.IsReadOnly] = false;
        row[SchemaTableColumn.DataType] = GetFieldType(n);
        row[SchemaTableOptionalColumn.IsHidden] = false;

        strColumn = _command.Connection._sql.ColumnOriginalName(_activeStatement, n);
        if (String.IsNullOrEmpty(strColumn) == false) row[SchemaTableColumn.BaseColumnName] = strColumn;
        
        row[SchemaTableColumn.IsExpression] = String.IsNullOrEmpty(strColumn);
        row[SchemaTableColumn.IsAliased] = (String.Compare(GetName(n), strColumn, true, CultureInfo.InvariantCulture) != 0);

        temp = _command.Connection._sql.ColumnTableName(_activeStatement, n);
        if (String.IsNullOrEmpty(temp) == false) row[SchemaTableColumn.BaseTableName] = temp;

        temp = _command.Connection._sql.ColumnDatabaseName(_activeStatement, n);
        if (String.IsNullOrEmpty(temp) == false) row[SchemaTableOptionalColumn.BaseCatalogName] = temp;

        string dataType = null;
        // If we have a table-bound column, extract the extra information from it
        if (String.IsNullOrEmpty(strColumn) == false)
        {
          string collSeq;
          bool bNotNull;
          bool bPrimaryKey;
          bool bAutoIncrement;
          string[] arSize;

          // Get the column meta data
          _command.Connection._sql.ColumnMetaData(
            (string)row[SchemaTableOptionalColumn.BaseCatalogName],
            (string)row[SchemaTableColumn.BaseTableName],
            strColumn,
            out dataType, out collSeq, out bNotNull, out bPrimaryKey, out bAutoIncrement);

          if (bNotNull || bPrimaryKey) row[SchemaTableColumn.AllowDBNull] = false;

          row[SchemaTableColumn.IsKey] = bPrimaryKey;
          row[SchemaTableOptionalColumn.IsAutoIncrement] = bAutoIncrement;

          // For types like varchar(50) and such, extract the size
          arSize = dataType.Split('(');
          if (arSize.Length > 1)
          {
            dataType = arSize[0];
            arSize = arSize[1].Split(')');
            if (arSize.Length > 1)
            {
              arSize = arSize[0].Split(',', '.');
              if (GetSQLiteType(n).Type == DbType.String || GetSQLiteType(n).Type == DbType.Binary)
              {
                row[SchemaTableColumn.ColumnSize] = Convert.ToInt32(arSize[0], CultureInfo.InvariantCulture);
              }
              else
              {
                row[SchemaTableColumn.NumericPrecision] = Convert.ToInt32(arSize[0], CultureInfo.InvariantCulture);
                if (arSize.Length > 1)
                  row[SchemaTableColumn.NumericScale] = Convert.ToInt32(arSize[1], CultureInfo.InvariantCulture);
              }
            }
          }

          if (wantDefaultValue)
          {
            // Determine the default value for the column, which sucks because we have to query the schema for each column
            using (SQLiteCommand cmdTable = new SQLiteCommand(String.Format(CultureInfo.InvariantCulture, "PRAGMA [{0}].TABLE_INFO([{1}])",
              row[SchemaTableOptionalColumn.BaseCatalogName],
              row[SchemaTableColumn.BaseTableName]
              ), _command.Connection))
            using (DbDataReader rdTable = cmdTable.ExecuteReader())
            {
              // Find the matching column
              while (rdTable.Read())
              {
                if (String.Compare((string)row[SchemaTableColumn.BaseColumnName], rdTable.GetString(1), true, CultureInfo.InvariantCulture) == 0)
                {
                  if (rdTable.IsDBNull(4) == false)
                    row[SchemaTableOptionalColumn.DefaultValue] = rdTable[4];

                  break;
                }
              }