private IEnumerable<ParadoxRecord> Enumerate(ParadoxCondition condition, ushort blockId, int indexLevel)
{
if (indexLevel == 0)
{
var block = this.table.GetBlock(blockId);
for (int i=0; i<block.RecordCount; i++)
{
var rec = block[i];
if (condition.IsDataOk(rec))
{
yield return rec;
}
}
}
else
{
var block = this.GetBlock(blockId);
var blockIdFldIndex = this.FieldCount - 3;
for (int i = 0; i < block.RecordCount; i++)
{
var rec = block[i];
if (condition.IsIndexPossible(rec, i < block.RecordCount-1 ? block[i + 1] : null))
{
var qry = Enumerate(condition, (ushort)((short) rec.DataValues[blockIdFldIndex]-1), indexLevel - 1);
foreach (var dataRec in qry)
{
yield return dataRec;
}
}
}
}
}
private IEnumerable <ParadoxRecord> Enumerate(ParadoxCondition condition, ushort blockId, int indexLevel)
{
if (indexLevel == 0)
{
var block = this.table.GetBlock(blockId);
for (int i = 0; i < block.RecordCount; i++)
{
var rec = block[i];
if (condition.IsDataOk(rec))
{
yield return(rec);
}
}
}
else
{
var block = this.GetBlock(blockId);
var blockIdFldIndex = this.FieldCount - 3;
for (int i = 0; i < block.RecordCount; i++)
{
var rec = block[i];
if (condition.IsIndexPossible(rec, i < block.RecordCount - 1 ? block[i + 1] : null))
{
var qry = Enumerate(condition, (ushort)((short)rec.DataValues[blockIdFldIndex] - 1), indexLevel - 1);
foreach (var dataRec in qry)
{
yield return(dataRec);
}
}
}
}
}
/// <summary>
/// 获取数据库游标
/// </summary>
/// <param name="tableName">要查询的数据库表名称</param>
/// <param name="where">数据库查询条件</param>
/// <param name="useIndex">是否使用数据库索引</param>
/// <returns></returns>
public ParadoxDataReader ExecuteQuery(string tableName, ParadoxCondition where, bool useIndex)
{
var table = GetParadoxTable(tableName);
IEnumerable<ParadoxRecord> qry = null;
if (useIndex)
{
var index = table.PrimaryKeyIndex; // index
qry = index.Enumerate(where); // query
}
else
{
qry = table.Enumerate(where); // query
}
return new ParadoxDataReader(table, qry); // reader
}
// modified by zsl: use Query Condition instead of 'Predicate<ParadoxRecord> where'
//public IEnumerable<ParadoxRecord> Enumerate(Predicate<ParadoxRecord> where)
public IEnumerable <ParadoxRecord> Enumerate(ParadoxCondition condition)
{
for (int blockId = 0; blockId < this.fileBlocks; blockId++)
{
var block = this.GetBlock(blockId);
for (var recId = 0; recId < block.RecordCount; recId++)
{
var rec = block[recId];
//if (where == null || where(rec))
if (condition == null || condition.IsDataOk(rec))
{
yield return(rec);
}
}
}
}
// modified by zsl: use Query Condition instead of 'Predicate<ParadoxRecord> where'
//public IEnumerable<ParadoxRecord> Enumerate(Predicate<ParadoxRecord> where)
public IEnumerable<ParadoxRecord> Enumerate(ParadoxCondition condition)
{
for (int blockId = 0; blockId < this.fileBlocks; blockId++)
{
var block = this.GetBlock(blockId);
for (var recId = 0; recId < block.RecordCount; recId++)
{
var rec = block[recId];
//if (where == null || where(rec))
if (condition == null || condition.IsDataOk(rec))
{
yield return rec;
}
}
}
}
public QueryArgs(string table, ParadoxCondition condition, string tag, string id)
{
this.TableName = table;
this.Condition = condition;
this.TagName = tag;
this.IDName = id;
}
public QueryArgs(string table, string tag, string id)
{
this.TableName = table;
this.Condition = new NullCondtion();
this.TagName = tag;
this.IDName = id;
}
public QueryArgs(string table)
{
this.TableName = table;
this.Condition = new NullCondtion();
this.TagName = "";
this.IDName = "";
}
public IEnumerable<ParadoxRecord> Enumerate(ParadoxCondition condition)
{
return Enumerate(condition, (ushort)(this.pxRootBlockId-1), this.pxLevelCount);
}
protected Multiple(ParadoxCondition[] subConditions)
{
SubConditions = subConditions;
}
public IEnumerable <ParadoxRecord> Enumerate(ParadoxCondition condition)
{
return(Enumerate(condition, (ushort)(this.pxRootBlockId - 1), this.pxLevelCount));
}
/// <summary>
/// 获取数据库游标
/// </summary>
/// <param name="tableName">要查询的数据库表名称</param>
/// <param name="where">数据库查询条件</param>
/// <returns></returns>
public ParadoxDataReader ExecuteQuery(string tableName, ParadoxCondition where)
{
return ExecuteQuery(tableName, where, true);
}