/// <summary>
/// Gets a value of the specified column of the current row.
/// </summary>
/// <param name="column">The column.</param>
/// <returns>A column value.</returns>
/// <exception cref="ArgumentNullException"><paramref name="column"/> is <c>null</c>.</exception>
/// <exception cref="ArgumentOutOfRangeException">
/// The column is from different table instance.
/// </exception>
/// <exception cref="InvalidOperationException">
/// No row is loaded. The <see cref="Read"/> method returned <c>false</c> or it has not been called yet.<br />
/// -- or --<br />
/// The underlying stream is non-seekable and columns are read out of order.
/// </exception>
/// <exception cref="ObjectDisposedException">The parent table is disposed.</exception>
public virtual object GetValue(IColumn column)
{
CheckColumn(column);
var columnBase = (Column)column;
byte[] fieldCache = null;
MemoCache memoItem = null;
if (columnBase.dbfType == NativeColumnType.Memo)
{ // for detached mode and performance: return cached memo value if available or read it and store to cache
Debug.Assert(memoCache != null);
memoItem = Array.Find(memoCache, (c => c.column == column));
Debug.Assert(memoItem != null);
fieldCache = memoItem.data;
}
object ret = columnBase.LoadValueAsObject(_buffer, ref fieldCache);
if (memoItem != null)
{
memoItem.data = fieldCache;
}
return(ret);
}
/// <summary>
/// Gets a value of the specified column of the current row.
/// </summary>
/// <typeparam name="T">The column type.</typeparam>
/// <param name="column">The column.</param>
/// <returns>A column value.</returns>
/// <exception cref="ArgumentNullException"><paramref name="column"/> is <c>null</c>.</exception>
/// <exception cref="ArgumentOutOfRangeException">
/// The column is from different table instance.
/// </exception>
/// <exception cref="InvalidOperationException">
/// No row is loaded. The <see cref="Read"/> method returned <c>false</c> or it has not been called yet.<br />
/// -- or --<br />
/// The underlying stream is non-seekable and columns are read out of order.
/// </exception>
/// <exception cref="ObjectDisposedException">The parent table is disposed.</exception>
public T GetValue <T>(IColumn column)
{
CheckColumn(column);
if (!typeof(T).IsAssignableFrom(column.type))
{
throw new ArgumentOutOfRangeException("column", "The column's type does not match the method's return type.");
}
//if (column.type != typeof(T))
//{
// throw new ArgumentOutOfRangeException("column", "The column's type does not match the method's return type.");
//}
var typedColumn = (Column <T>)column;
byte[] fieldCache = null;
MemoCache memoItem = null;
if (typedColumn.dbfType == NativeColumnType.Memo)
{ // for detached mode and performance: return cached memo value if available or read it and store to cache
Debug.Assert(memoCache != null);
memoItem = Array.Find(memoCache, (c => c.column == typedColumn));
Debug.Assert(memoItem != null);
fieldCache = memoItem.data;
}
T ret = typedColumn.LoadValue(_buffer, ref fieldCache);
if (memoItem != null)
{
memoItem.data = fieldCache;
}
return(ret);
}
internal const int forInsert_recNoValue = int.MinValue; // value of recNo if this row wait for insert to a DbfTable
/// <summary>
/// Contructor of row.
/// </summary>
/// <param name="recNo">No. of row in dbf file (first is 0)</param>
/// <param name="buffer">bytes of entire record content</param>
/// <param name="columns">DbfTable header information for detached mode</param>
protected internal DbfRow(int recNo, byte[] buffer, IColumn[] columns, Guid dbfTableClassID)
{
this._columns = columns;
this._buffer = buffer;
this._recNo = recNo;
this._dbfTableClassID = dbfTableClassID;
//
var memoColumns = Array.FindAll(_columns, (c => c.dbfType == NativeColumnType.Memo));
if (memoColumns.Length > 0)
{
memoCache = new MemoCache[memoColumns.Length];
for (int i = 0; i < memoColumns.Length; i++)
{
memoCache[i] = new MemoCache();
memoCache[i].column = memoColumns[i]; // Identifier of memo field
}
}
}
