public bool Create(ushort[] fields)
{
uint i;
if (fields == null)
{
return(false);
}
DBFTable parent = _parent;
if (fields.Any(m => m > parent.Header.Field.Length))
{
return(false);
}
Clear();
_indexFields = fields;
_items = new DBFIndexItem[_parent.Record.Length];
var tempIndex = new DBFIndexItem[_parent.Record.Length];
for (i = 0; i < _parent.Record.Length; i++)
{
_items[i].RecNum = i;
string sKey = string.Empty;
// ReSharper disable LoopCanBeConvertedToQuery
foreach (int m in fields)
{
sKey = sKey + _parent.Record[i].Field[m];
}
// ReSharper restore LoopCanBeConvertedToQuery
// ReSharper disable ConvertIfStatementToConditionalTernaryExpression
if (DBFIndexItem.ItemHandler == null)
{
_items[i].Key = sKey;
}
// ReSharper restore ConvertIfStatementToConditionalTernaryExpression
else
{
_items[i].Key = DBFIndexItem.ItemHandler(sKey); //"";
}
}
//первичная сортировка
for (i = 0; i < _items.Length - 1; i += 2)
{
if (_items[i].Key == _items[i + 1].Key)
{
tempIndex[i] = _items[i];
tempIndex[i + 1] = _items[i + 1];
}
else
{
tempIndex[i] = _items[i + 1];
tempIndex[i + 1] = _items[i];
}
}
if (i < _items.Length)
{
tempIndex[i] = _items[i];
}
//инициализация
DBFIndexItem[] pa = tempIndex;
DBFIndexItem[] pb = _items;
uint blockSize = 2;
//основная сортировка
while (blockSize < _items.Length) //perform while block size are less then array size
{
i = 0; //setting base itemses for left block
uint k = 0;
while (i < _items.Length)
{
uint j;
if ((i + blockSize) >= _items.Length)
{
for (j = 0; j < (_items.Length - i); j++)
{
pb[k + j] = pa[i + j];
}
k += (uint)(_items.Length - i);
break;
}
uint lSize = blockSize;
uint rSize;
if ((i + blockSize + blockSize) < _items.Length)
{
rSize = blockSize;
}
else
{
rSize = (uint)(_items.Length - i - blockSize); //set length of right block
}
j = i + lSize; //set base items for right block
while ((lSize > 0) && (rSize > 0)) //starting merging of blocks
{
if (pa[i].Key.CompareTo(pa[j].Key) <= 0)
{
pb[k] = pa[i];
i++;
lSize--;
}
else
{
pb[k] = pa[j];
j++;
rSize--;
}
k++;
}
if (rSize == 0)
{
for (uint t = 0; t < lSize; t++)
{
pb[k + t] = pa[i + t];
}
i += lSize;
k += lSize;
}
if (lSize == 0)
{
for (uint t = 0; t < rSize; t++)
{
pb[k + t] = pa[j + t];
}
j += rSize;
k += rSize;
}
i += blockSize;
}
blockSize *= 2; //double size of block
var cb = pb;
pb = pa;
pa = cb; //switch input and output arrays
}
//if( _items != pa )
_items = pa;
return(true);
}
public bool Create( ushort[] fields )
{
uint i;
if( fields == null ) return false;
DBFTable parent = _parent;
if (fields.Any(m => m > parent.Header.Field.Length))
return false;
Clear();
_indexFields = fields;
_items = new DBFIndexItem[_parent.Record.Length];
var tempIndex = new DBFIndexItem[_parent.Record.Length];
for( i = 0; i < _parent.Record.Length; i++ )
{
_items[i].RecNum = i;
string sKey = string.Empty;
// ReSharper disable LoopCanBeConvertedToQuery
foreach( int m in fields ) sKey = sKey + _parent.Record[i].Field[m];
// ReSharper restore LoopCanBeConvertedToQuery
// ReSharper disable ConvertIfStatementToConditionalTernaryExpression
if( DBFIndexItem.ItemHandler == null ) _items[i].Key = sKey;
// ReSharper restore ConvertIfStatementToConditionalTernaryExpression
else _items[i].Key = DBFIndexItem.ItemHandler(sKey);//"";
}
//первичная сортировка
for( i = 0; i < _items.Length - 1; i += 2 )
if( _items[i].Key == _items[i + 1].Key )
{
tempIndex[i] = _items[i];
tempIndex[i + 1] = _items[i + 1];
}
else
{
tempIndex[i] = _items[i + 1];
tempIndex[i + 1] = _items[i];
}
if( i < _items.Length ) tempIndex[i] = _items[i];
//инициализация
DBFIndexItem[] pa = tempIndex;
DBFIndexItem[] pb = _items;
uint blockSize = 2;
//основная сортировка
while( blockSize < _items.Length ) //perform while block size are less then array size
{
i = 0; //setting base itemses for left block
uint k = 0;
while( i < _items.Length )
{
uint j;
if( (i + blockSize) >= _items.Length )
{
for( j = 0; j < (_items.Length - i); j++ ) pb[k + j] = pa[i + j];
k += (uint)(_items.Length - i);
break;
}
uint lSize = blockSize;
uint rSize;
if( (i + blockSize + blockSize) < _items.Length ) rSize = blockSize;
else rSize = (uint)(_items.Length - i - blockSize); //set length of right block
j = i + lSize; //set base items for right block
while( (lSize > 0) && (rSize > 0) ) //starting merging of blocks
{
if( pa[i].Key.CompareTo(pa[j].Key) <= 0 )
{
pb[k] = pa[i];
i++;
lSize--;
}
else
{
pb[k] = pa[j];
j++;
rSize--;
}
k++;
}
if( rSize == 0 )
{
for( uint t = 0; t < lSize; t++ ) pb[k + t] = pa[i + t];
i += lSize;
k += lSize;
}
if( lSize == 0 )
{
for( uint t = 0; t < rSize; t++ ) pb[k + t] = pa[j + t];
j += rSize;
k += rSize;
}
i += blockSize;
}
blockSize *= 2; //double size of block
var cb = pb;
pb = pa;
pa = cb; //switch input and output arrays
}
//if( _items != pa )
_items = pa;
return true;
}
