C# Hashtable的用法

public void Add(Object item)
{
if (!data.ContainsValue(item))
data.Add(Hash(item), item);
}

private string Hash(Object item)
{
char[] chars;
string s = item.ToString();
int hashValue = 0;
chars = s.ToCharArray();
for (int i = 0; i <= chars.GetUpperBound(0); i++)
hashValue += (int)chars[i];
return hashValue.ToString();
}

//这是移除的方法
public void Remove(Object item)
{
data.Remove(Hash(item));
}
//确定数量多少的方法
public int Size()
{
return data.Count;
}

public CSet Union(CSet aSet)
{
CSet tempSet = new CSet();
foreach (Object hashObject in data.Keys)
tempSet.Add(this.data[hashObject]);
foreach (Object hashObject in aSet.data.Keys)
if (!(this.data.ContainsKey(hashObject)))
tempSet.Add(aSet.data[hashObject]);
return tempSet;
}

public CSet Intersection(CSet aSet)
{
CSet tempSet = new CSet();
foreach (Object hashObject in data.Keys)
if (aSet.data.Contains(hashObject))
tempSet.Add(aSet.data[hashObject]);
tempSet.Add(aSet.GetValue(hashObject))
return tempSet;
}

public bool Subset(CSet aSet)
{
if (this.Size() > aSet.Size())
return false;
else
foreach (Object key in this.data.Keys)
if (!(aSet.data.Contains(key)))
return false;
return true;
}

public CSet Difference(CSet aSet)
{
CSet tempSet = new CSet();
foreach (Object hashObject in data.Keys) if (!(aSet.data.Contains(hashObject)))
tempSet.Add(data[hashObject]);
return tempSet;
}
public override string ToString()
{
string s = “”;
foreach (Object key in data.Keys)
s += data[key] + " ";
return s;
}