<分区>
如何将以下方法更改为递归方法:
public List<ScanItem> search(List<ScanItem> allItems)
{
List<ScanItem> rt = new List<ScanItem>();
foreach (ScanItem s in allItems)
{
if (s.IsDirectory)
{
rt.Add(s);
foreach (ScanItem s1 in ((ScanDir)s).Items)
{
if (s1.IsDirectory)
{
rt.Add(s1);
foreach (ScanItem s2 in ((ScanDir)s1).Items)
{
if (s2.IsDirectory)
{
rt.Add(s2);
foreach (ScanItem s3 in ((ScanDir)s2).Items)
{
if (s3.IsDirectory)
{
rt.Add(s3);
/// repeat until there are no more direcotries
}
else
if (s3.Name.Contains("Foo"))
rt.Add(s3);
}
}
else
if (s2.Name.Contains("Foo"))
rt.Add(s2);
}
}
else
if (s1.Name.Contains("Foo"))
rt.Add(s1);
}
}
else
if (s.Name.Contains("Foo"))
rt.Add(s);
}
return rt;
}
让我向您展示我是如何构建它的:
第一步:
public List<ScanItem> search(List<ScanItem> allItems)
{
List<ScanItem> rt = new List<ScanItem>();
foreach (ScanItem s in allItems)
{
if (s.IsDirectory)
{
rt.Add(s);
}
else
if (s.Name.Contains("Foo"))
rt.Add(s);
}
return rt;
}
第二步:
public List<ScanItem> search(List<ScanItem> allItems)
{
List<ScanItem> rt = new List<ScanItem>();
foreach (ScanItem s in allItems)
{
if (s.IsDirectory)
{
rt.Add(s);
foreach (ScanItem s1 in ((ScanDir)s).Items)
{
if (s1.IsDirectory)
{
rt.Add(s1);
}
else
if (s1.Name.Contains("Foo"))
rt.Add(s1);
}
}
else
if (s.Name.Contains("Foo"))
rt.Add(s);
}
return rt;
}
第 3 步:
public List<ScanItem> search(List<ScanItem> allItems)
{
List<ScanItem> rt = new List<ScanItem>();
foreach (ScanItem s in allItems)
{
if (s.IsDirectory)
{
rt.Add(s);
foreach (ScanItem s1 in ((ScanDir)s).Items)
{
if (s1.IsDirectory)
{
rt.Add(s1);
foreach (ScanItem s2 in ((ScanDir)s1).Items)
{
if (s2.IsDirectory)
{
rt.Add(s2);
}
else
if (s2.Name.Contains("Foo"))
rt.Add(s2);
}
}
else
if (s1.Name.Contains("Foo"))
rt.Add(s1);
}
}
else
if (s.Name.Contains("Foo"))
rt.Add(s);
}
return rt;
}
第 4 步:
public List<ScanItem> search(List<ScanItem> allItems)
{
List<ScanItem> rt = new List<ScanItem>();
foreach (ScanItem s in allItems)
{
if (s.IsDirectory)
{
rt.Add(s);
foreach (ScanItem s1 in ((ScanDir)s).Items)
{
if (s1.IsDirectory)
{
rt.Add(s1);
foreach (ScanItem s2 in ((ScanDir)s1).Items)
{
if (s2.IsDirectory)
{
rt.Add(s2);
foreach (ScanItem s3 in ((ScanDir)s2).Items)
{
if (s3.IsDirectory)
{
rt.Add(s3);
}
else
if (s3.Name.Contains("Foo"))
rt.Add(s3);
}
}
else
if (s2.Name.Contains("Foo"))
rt.Add(s2);
}
}
else
if (s1.Name.Contains("Foo"))
rt.Add(s1);
}
}
else
if (s.Name.Contains("Foo"))
rt.Add(s);
}
return rt;
}
请注意，我一直在复制:
foreach (ScanItem s3 in ((ScanDir)s2).Items)
{
if (s3.IsDirectory)
{
rt.Add(s3);
/// repeat until there are no more direcotries
}
else
if (s3.Name.Contains("Foo"))
rt.Add(s3);
}