///<summary>
/// Edit the specified rows via a client supplied callback
///</summary>
///<param name="indices">rows to edit</param>
///<param name="rowCallback">client supplied callback</param>
public virtual void Edit(IEnumerable<int> indices, RowEditEvent rowCallback)
{
var fi = new FileInfo(_fileName);
if ((int)fi.Length == _headerLength)
{
// The file is empty, so just return
return;
}
foreach (Field field in _columns)
{
field.NumberConverter = new NumberConverter(field.Length, field.DecimalCount);
}
var fields = new Fields(_columns);
using (var myStream = new FileStream(_fileName, FileMode.Open, FileAccess.ReadWrite, FileShare.ReadWrite, _recordLength))
{
var e = new RowEditEventArgs(_recordLength - 1, fields);
foreach (int rowIndex in indices)
{
int strt = GetFileIndex(rowIndex);
long offset = _headerLength + 1 + strt * _recordLength;
myStream.Seek(offset, SeekOrigin.Begin);
myStream.Read(e.ByteContent, 0, _recordLength - 1);
e.RowNumber = rowIndex;
e.Modified = false;
if (rowCallback(e))
return;
if (e.Modified)
{
myStream.Seek(offset, SeekOrigin.Begin);
myStream.Write(e.ByteContent, 0, _recordLength - 1);
}
}
}
}
/// <summary>
/// Constructor
/// </summary>
/// <param name="recordLength"></param>
/// <param name="columns"></param>
public RowEditEventArgs(int recordLength, Fields columns)
{
Columns = columns;
ByteContent = new byte[recordLength];
Modified = false;
}