//该方法将不同行细分为：修改、删除、新增类型；
private bool AddChanges(
ArrayList report,
int curDest,
int nextDest,
int curSource,
int nextSource)
{
bool retval = false;
int diffDest = nextDest - curDest;//下一个区域的索引减去当前区域索引（区域总共多少行？）
int diffSource = nextSource - curSource;
int minDiff = 0;
if (diffDest > 0)
{
if (diffSource > 0)
{
minDiff = Math.Min(diffDest, diffSource);
//curDest---新版本文件中区域块第一行的索引
//curSource --- 老版本文件中区域块第一行索引
//minDiff ---区域块中行数目
report.Add(DiffResultSpan.CreateReplace(curDest, curSource, minDiff));
//比如老版本10行，新版本5行；合并后10行不同，前5行是修改状态，后5行是新增状态
//minDiff = 5；
if (diffDest > diffSource)
{
curDest += minDiff;
report.Add(DiffResultSpan.CreateAddDestination(curDest, diffDest - diffSource));
}
else//比如老版本3行，新版本5行；合并后5行不同，前3行是修改状态，后2行是删除状态
//minDiff = 3;
{
if (diffSource > diffDest)
{
curSource += minDiff;
report.Add(DiffResultSpan.CreateDeleteSource(curSource, diffSource - diffDest));
}
}
}
else //diffSource == 0表示老版本没有行，新版本有，表示新增行
{
report.Add(DiffResultSpan.CreateAddDestination(curDest, diffDest));
}
retval = true;
}
else
{
if (diffSource > 0)
{
report.Add(DiffResultSpan.CreateDeleteSource(curSource, diffSource));
retval = true;
}
}
return(retval);
}
public ArrayList DiffReport()
{
ArrayList retval = new ArrayList();
int dcount = _destination.Count();
int scount = _source.Count();
//Deal with the special case of empty files
if (dcount == 0)
{
if (scount > 0)
{
retval.Add(DiffResultSpan.CreateDeleteSource(0, scount));
}
return(retval);
}
else
{
if (scount == 0)
{
retval.Add(DiffResultSpan.CreateAddDestination(0, dcount));
return(retval);
}
}
_matchList.Sort();
int curDest = 0;
int curSource = 0;
DiffResultSpan last = null;
//Process each match record
foreach (DiffResultSpan drs in _matchList)
{
if ((!AddChanges(retval, curDest, drs.DestIndex, curSource, drs.SourceIndex)) &&
(last != null))
{
last.AddLength(drs.Length);
}
else
{
retval.Add(drs);
}
curDest = drs.DestIndex + drs.Length;
curSource = drs.SourceIndex + drs.Length;
last = drs;
}
//Process any tail end data
AddChanges(retval, curDest, dcount, curSource, scount);
return(retval);
}
public DiffResultSpanCollection DiffReport()
{
DiffResultSpanCollection returnResultSpanCollection = new DiffResultSpanCollection();
int dcount = _dest.Count();
int scount = _source.Count();
//Deal with the special case of empty files
if (dcount == 0)
{
if (scount > 0)
{
returnResultSpanCollection.Add(DiffResultSpan.CreateDeleteSource(0, scount));
}
return(returnResultSpanCollection);
}
else
{
if (scount == 0)
{
returnResultSpanCollection.Add(DiffResultSpan.CreateAddDestination(0, dcount));
return(returnResultSpanCollection);
}
}
_matchList.Sort();
int curDest = 0;
int curSource = 0;
DiffResultSpan lastResultSpan = null;
//Process each match record
foreach (DiffResultSpan resultSpan in _matchList)
{
if ((!AddChanges(returnResultSpanCollection, curDest, resultSpan.DestIndex, curSource, resultSpan.SourceIndex)) &&
(lastResultSpan != null))
{
lastResultSpan.AddLength(resultSpan.Length);
}
else
{
returnResultSpanCollection.Add(resultSpan);
}
curDest = resultSpan.DestIndex + resultSpan.Length;
curSource = resultSpan.SourceIndex + resultSpan.Length;
lastResultSpan = resultSpan;
}
//Process any tail end data
AddChanges(returnResultSpanCollection, curDest, dcount, curSource, scount);
return(returnResultSpanCollection);
}
//添加不同行的区域块，从第一行到最后一行，相邻的行状态相同为一个区域块
//DiffReport返回参数解释：
//int DestIndex ---区域块第一行在新版本文件中的原来的索引
//SourceIndex ---区域块第一行在老版本文件中的原来的索引
//int Length ---当前区域块中的行的个数
//Status ---改区域块中所有行共同的状态（Add/Delete/Modify）
public ArrayList DiffReport()
{
ArrayList resultList = new ArrayList();//返回值
int dcount = _dest.Count();
int scount = _source.Count();
//处理空文件
if (dcount == 0)
{
if (scount > 0)
{
resultList.Add(DiffResultSpan.CreateDeleteSource(0, scount));
}
return(resultList);
}
else
{
if (scount == 0)
{
resultList.Add(DiffResultSpan.CreateAddDestination(0, dcount));
return(resultList);
}
}
//_matchList添加了相同行和不同行区域块，但是不同行又分为：新增、删除、修改三个状态没有区分
_matchList.Sort();
int curNewIndex = 0;
int curOldIndex = 0;
DiffResultSpan last = null;
//Process each match record
foreach (DiffResultSpan drs in _matchList)
{
if ((!AddChanges(resultList, curNewIndex, drs.DestIndex, curOldIndex, drs.SourceIndex)) &&
(last != null))
{
last.AddLength(drs.Length);
}
else
{
resultList.Add(drs);
}
curNewIndex = drs.DestIndex + drs.Length;//新版本当前区域块第一行的索引。
curOldIndex = drs.SourceIndex + drs.Length;
last = drs;
}
//Process any tail end data
AddChanges(resultList, curNewIndex, dcount, curOldIndex, scount);
return(resultList);
}
private bool AddChanges(
List <DiffResultSpan> report,
int curDest,
int nextDest,
int curSource,
int nextSource)
{
bool retval = false;
int diffDest = nextDest - curDest;
int diffSource = nextSource - curSource;
int minDiff = 0;
if (diffDest > 0)
{
if (diffSource > 0)
{
minDiff = Math.Min(diffDest, diffSource);
report.Add(DiffResultSpan.CreateReplace(curDest, curSource, minDiff));
if (diffDest > diffSource)
{
curDest += minDiff;
report.Add(DiffResultSpan.CreateAddDestination(curDest, diffDest - diffSource));
}
else
{
if (diffSource > diffDest)
{
curSource += minDiff;
report.Add(DiffResultSpan.CreateDeleteSource(curSource, diffSource - diffDest));
}
}
}
else
{
report.Add(DiffResultSpan.CreateAddDestination(curDest, diffDest));
}
retval = true;
}
else
{
if (diffSource > 0)
{
report.Add(DiffResultSpan.CreateDeleteSource(curSource, diffSource));
retval = true;
}
}
return(retval);
}