public Enumerator(XDictionary <TKey, TValue> content)
{
this.content = content;
number = 0;
index = -1;
}
internal ValuesCollection(XDictionary <TKey, TValue> content, TKey key)
{
this.content = content;
this.key = key;
hashCode = content.GetHashCode(key);
length = -1;
}
private static void SwitchObject <T>(this ILGenerator ILGen,
Action <ILGenerator> LdcValue,
LocalBuilder HashCodeLocal,
Action <ILGenerator> CallEquals,
XDictionary <int, List <CaseInfo <T> > > Cases,
Label DefaultLabel,
Action <ILGenerator, T> ldcCase,
int Begin,
int Index,
int End)
{
if (Begin > End)
{
return;
}
if (Begin == End)
{
ILGen.LoadLocal(HashCodeLocal);
ILGen.LoadConstant(Cases.GetEntry(Begin).Key);
ILGen.Emit(OpCodes.Bne_Un, DefaultLabel);
foreach (var Item in Cases.GetEntry(Begin).Value)
{
LdcValue(ILGen);
ldcCase(ILGen, Item.Value);
CallEquals(ILGen);
ILGen.Emit(OpCodes.Brtrue, Item.Label);
}
ILGen.Emit(OpCodes.Br, DefaultLabel);
return;
}
if (Begin + 1 == End)
{
var EndLabel = ILGen.DefineLabel();
ILGen.LoadLocal(HashCodeLocal);
ILGen.LoadConstant(Cases.GetEntry(Begin).Key);
ILGen.Emit(OpCodes.Bne_Un, EndLabel);
foreach (var Item in Cases.GetEntry(Begin).Value)
{
LdcValue(ILGen);
ldcCase(ILGen, Item.Value);
CallEquals(ILGen);
ILGen.Emit(OpCodes.Brtrue, Item.Label);
}
ILGen.MarkLabel(EndLabel);
ILGen.LoadLocal(HashCodeLocal);
ILGen.LoadConstant(Cases.GetEntry(End).Key);
ILGen.Emit(OpCodes.Bne_Un, DefaultLabel);
foreach (var Item in Cases.GetEntry(End).Value)
{
LdcValue(ILGen);
ldcCase(ILGen, Item.Value);
CallEquals(ILGen);
ILGen.Emit(OpCodes.Brtrue, Item.Label);
}
ILGen.Emit(OpCodes.Br, DefaultLabel);
return;
}
var GtLabel = ILGen.DefineLabel();
ILGen.LoadLocal(HashCodeLocal);
ILGen.LoadConstant(Cases.GetEntry(Index).Key);
ILGen.Emit(OpCodes.Bgt, GtLabel);
SwitchObject(
ILGen,
LdcValue,
HashCodeLocal,
CallEquals,
Cases,
DefaultLabel,
ldcCase,
Begin,
(Begin + Index) / 2,
Index);
ILGen.MarkLabel(GtLabel);
SwitchObject(
ILGen,
LdcValue,
HashCodeLocal,
CallEquals,
Cases,
DefaultLabel,
ldcCase,
Index + 1,
(Index + 1 + End) / 2,
End);
}
/// <summary>
/// 生成指定类型的 Switch 代码块。
/// </summary>
/// <typeparam name="T">指定类型</typeparam>
/// <param name="iLGen">ILGenerator IL 指令生成器</param>
/// <param name="emitLdcValue">生成加载 Switch 参数的指令的委托</param>
/// <param name="getHashCodeMethod">获取 HashCode 值的方法，参数签名: int(T)</param>
/// <param name="equalsMethod">比例两个值的方法，参数签名: bool (T, T)</param>
/// <param name="cases">case 标签块集合</param>
/// <param name="defaultLabel">默认标签块</param>
/// <param name="ldcCaseValue">生成加载指定 Case 块值的指定的委托</param>
public static void Switch <T>(this ILGenerator iLGen,
Action <ILGenerator> emitLdcValue,
MethodInfo getHashCodeMethod,
MethodInfo equalsMethod,
CaseInfo <T>[] cases,
Label defaultLabel,
Action <ILGenerator, T> ldcCaseValue)
{
cases = (CaseInfo <T>[])cases.Clone();
if (getHashCodeMethod.IsStatic)
{
for (int i = 0; i < cases.Length; i++)
{
cases[i].HashCode = (int)getHashCodeMethod.Invoke(null, new object[] { cases[i].Value });
}
}
else
{
for (int i = 0; i < cases.Length; i++)
{
cases[i].HashCode = (int)getHashCodeMethod.Invoke(cases[i].Value, null);
}
}
Array.Sort(cases);
var GroupedCases = new XDictionary <int, List <CaseInfo <T> > >();
foreach (var Item in cases)
{
List <CaseInfo <T> > Items;
GroupedCases.TryGetValue(Item.HashCode, out Items);
if (Items == null)
{
Items = new List <CaseInfo <T> >();
Items.Add(Item);
GroupedCases.Add(Item.HashCode, Items);
}
else
{
Items.Add(Item);
}
}
var HashCodeLocal = iLGen.DeclareLocal(typeof(int));
emitLdcValue(iLGen);
iLGen.Emit(OpCodes.Call, getHashCodeMethod);
iLGen.StoreLocal(HashCodeLocal);
SwitchObject(
iLGen,
emitLdcValue,
HashCodeLocal,
(EqILGen) =>
{
EqILGen.Emit(OpCodes.Call, equalsMethod);
},
GroupedCases,
defaultLabel,
ldcCaseValue,
0,
(GroupedCases.Count - 1) / 2,
GroupedCases.Count - 1);
}
