public KeyInfoBase(
MemberInfo[] entityKeyMembers,
SortOrder[] sortOrders,
IComparer <TKey> keyComparer,
IKeyInfoHelper helper)
{
this.entityKeyMembers = entityKeyMembers;
if (sortOrders == null)
{
sortOrders = Enumerable
.Repeat(SortOrder.Ascending, helper.GetMemberCount())
.ToArray();
}
this.sortOrders = sortOrders;
this.keyComparer = keyComparer;
this.keySelector = KeyExpressionHelper
.CreateKeySelector <TEntity, TKey>(entityKeyMembers, helper)
.Compile();
this.keyEmptinessDetector = KeyExpressionHelper
.CreateKeyEmptinessDetector <TEntity, TKey>(helper)
.Compile();
}
public bool TryCreateKeyInfo <TEntity, TKey>(
Expression <Func <TEntity, TKey> > keySelector,
out IKeyInfo <TEntity, TKey> result)
where TEntity : class
{
Expression body = keySelector.Body;
Type keyType = body.Type;
if (!typeof(DataRow).IsAssignableFrom(body.Type))
{
result = null;
return(false);
}
IKeyInfoHelper helper = DataRowKeyInfo <TEntity, TKey> .KeyInfoHelper;
MemberInfo[] keyMembers;
if (!helper.TryParseKeySelectorExpression(keySelector.Body, true, out keyMembers))
{
result = null;
return(false);
}
result = new DataRowKeyInfo <TEntity, TKey>(keyMembers);
return(true);
}
public static Expression CreateKeyConversionExpression(
Expression source,
MemberInfo[] toMembers,
int[] mapping,
IKeyInfoHelper from,
IKeyInfoHelper to)
{
int memberCount = mapping.Length;
Expression[] factoryArgs = new Expression[memberCount];
for (int i = 0; i < memberCount; i++)
{
Type requestedType = ReflectionHelper.GetMemberType(toMembers[i]);
Expression arg = from.CreateKeyMemberSelectorExpression(source, mapping[i]);
if (arg.Type != requestedType)
{
arg = Expression.Convert(arg, requestedType);
}
factoryArgs[i] = arg;
}
return(to.CreateKeyFactoryExpression(factoryArgs));
}
public KeyInfoBase(
Expression <Func <TEntity, TKey> > keySelector,
SortOrder[] sortOrders,
IComparer <TKey> keyComparer,
IKeyInfoHelper helper)
: this(ParseSelector(keySelector, helper), sortOrders, keyComparer, helper)
{
}
private static MemberInfo[] ParseSelector(
Expression <Func <TEntity, TKey> > selector,
IKeyInfoHelper helper)
{
if (!helper.TryParseKeySelectorExpression(
selector.Body,
true,
out MemberInfo[] result))
public static Expression <Func <TKey, bool> > CreateKeyEmptinessDetector <TEntity, TKey>(
IKeyInfoHelper helper)
{
ParameterExpression param = Expression.Parameter(typeof(TKey));
Expression body = CreateKeyEmptinessDetector(param, helper);
return(Expression.Lambda <Func <TKey, bool> >(body, param));
}
public static Expression <Func <TEntity, TKey> > CreateKeySelector <TEntity, TKey>(
MemberInfo[] entityMembers,
IKeyInfoHelper helper)
{
ParameterExpression param = Expression.Parameter(typeof(TEntity));
Expression body = CreateKeySelector(param, entityMembers, helper);
return(Expression.Lambda <Func <TEntity, TKey> >(body, param));
}
public bool TryCreateKeyInfoHelper(Type keyType, out IKeyInfoHelper result)
{
if (!typeof(DataRow).IsAssignableFrom(keyType))
{
result = null;
return(false);
}
result = new DataRowKeyInfoHelper(keyType);
return(true);
}
public bool TryCreateKeyInfoHelper(
Type keyType,
out IKeyInfoHelper result)
{
if (!ReflectionHelper.IsAnonymousType(keyType))
{
result = null;
return(false);
}
result = new AnonymousTypeKeyInfoHelper(keyType);
return(true);
}
public bool TryCreateKeyInfoHelper(
Type keyType,
out IKeyInfoHelper result)
{
if (!ValidateType(keyType))
{
result = null;
return(false);
}
result = new PrimitiveKeyInfoHelper(keyType);
return(true);
}
public bool TryCreateKeyInfo <TEntity, TKey>(
Expression <Func <TEntity, TKey> > keySelector,
out IKeyInfo <TEntity, TKey> result) where TEntity : class
{
if (!ValidateType(typeof(TKey)))
{
result = null;
return(false);
}
IKeyInfoHelper helper = PrimitiveKeyInfo <TEntity, TKey> .KeyInfoHelper;
if (!helper.TryParseKeySelectorExpression(keySelector.Body, true, out MemberInfo[] members))
public static Expression CreateKeySelector(
Expression source,
MemberInfo[] entityMembers,
IKeyInfoHelper helper)
{
Expression[] memberAccess = new Expression[entityMembers.Length];
for (int i = 0; i < entityMembers.Length; i++)
{
memberAccess[i] = Expression.MakeMemberAccess(source, entityMembers[i]);
}
Expression body = helper.CreateKeyFactoryExpression(memberAccess);
return(body);
}
private static MemberInfo[] ParseSelector(
Expression <Func <TEntity, TKey> > selector,
IKeyInfoHelper helper)
{
MemberInfo[] result = null;
if (!helper.TryParseKeySelectorExpression(
selector.Body,
true,
out result))
{
throw new ArgumentException(
ExceptionMessages.InvalidKeySelector,
"keySelector");
}
return(result);
}
public bool TryCreateKeyInfoHelper(
Type keyType,
out IKeyInfoHelper result)
{
result = null;
bool success = false;
foreach (IKeyInfoService factory in this.factories)
{
if (factory.TryCreateKeyInfoHelper(keyType, out result))
{
success = true;
break;
}
}
return(success);
}
private static Func <TFrom, TTo> CreateConversion <TFrom, TTo>(
IKeyInfo <TFrom> fromKeyInfo,
IKeyInfo <TTo> toKeyInfo,
int[] mapping)
{
IKeyInfoHelper from = GetKeyInfoHelper(fromKeyInfo);
IKeyInfoHelper to = GetKeyInfoHelper(toKeyInfo);
ParameterExpression keyParam = Expression.Parameter(fromKeyInfo.KeyType);
Expression body =
KeyExpressionHelper.CreateKeyConversionExpression(
keyParam,
toKeyInfo.EntityKeyMembers,
mapping,
from,
to);
return(Expression.Lambda <Func <TFrom, TTo> >(body, keyParam).Compile());
}
protected override Expression VisitMethodCall(MethodCallExpression node)
{
if (!node.Method.IsGenericMethod ||
node.Method.GetGenericMethodDefinition() != this.Original)
{
// Not GroupJoin
return(base.VisitMethodCall(node));
}
if (!(node.Arguments[1] is ConstantExpression secondExpression))
{
// Not constant expression
return(base.VisitMethodCall(node));
}
if (!(secondExpression.Value is ITable table))
{
// Not table
return(base.VisitMethodCall(node));
}
LambdaExpression secondKeySelector =
ExpressionHelper.SkipQuoteNode(node.Arguments[3]) as LambdaExpression;
Type keyType = secondKeySelector.Body.Type;
IKeyInfoHelper helper = this.GetKeyInfoHelper(keyType);
if (helper == null)
{
// Cannot detect key type
return(base.VisitMethodCall(node));
}
// Try to parse expression
if (!helper.TryParseKeySelectorExpression(
secondKeySelector.Body,
false,
out MemberInfo[] keyMembers))
public static Expression CreateKeyEmptinessDetector(
Expression source,
IKeyInfoHelper helper)
{
Expression body = null;
int memberCount = helper.GetMemberCount();
for (int i = 0; i < memberCount; i++)
{
Expression member = helper.CreateKeyMemberSelectorExpression(source, i);
Type memberType = member.Type;
if (ReflectionHelper.IsNullable(memberType))
{
Expression equalityTest =
Expression.Equal(
member,
Expression.Constant(null, memberType));
if (body == null)
{
body = equalityTest;
}
else
{
body = Expression.Or(body, equalityTest);
}
}
}
// If all the members of the anonymous type is not nullable, the body expression
// is null at this point
if (body == null)
{
body = Expression.Constant(false);
}
return(body);
}
public bool TryCreateKeyInfo <TEntity, TKey>(
Expression <Func <TEntity, TKey> > keySelector,
out IKeyInfo <TEntity, TKey> result) where TEntity : class
{
if (!ReflectionHelper.IsAnonymousType(typeof(TKey)))
{
result = null;
return(false);
}
IKeyInfoHelper helper = AnonymousTypeKeyInfo <TEntity, TKey> .KeyInfoHelper;
MemberInfo[] members;
if (!helper.TryParseKeySelectorExpression(keySelector.Body, true, out members))
{
result = null;
return(false);
}
result = new AnonymousTypeKeyInfo <TEntity, TKey>(members);
return(true);
}
protected override Expression VisitMethodCall(MethodCallExpression node)
{
if (!node.Method.IsGenericMethod ||
node.Method.GetGenericMethodDefinition() != this.Original)
{
// Not GroupJoin
return(base.VisitMethodCall(node));
}
ConstantExpression secondExpression = node.Arguments[1] as ConstantExpression;
if (secondExpression == null)
{
// Not constant expression
return(base.VisitMethodCall(node));
}
ITable table = secondExpression.Value as ITable;
if (table == null)
{
// Not table
return(base.VisitMethodCall(node));
}
LambdaExpression secondKeySelector =
ExpressionHelper.SkipQuoteNode(node.Arguments[3]) as LambdaExpression;
Type keyType = secondKeySelector.Body.Type;
IKeyInfoHelper helper = this.GetKeyInfoHelper(keyType);
if (helper == null)
{
// Cannot detect key type
return(base.VisitMethodCall(node));
}
// Try to parse expression
MemberInfo[] keyMembers;
if (!helper.TryParseKeySelectorExpression(
secondKeySelector.Body,
false,
out keyMembers))
{
// Cannot parse key
return(base.VisitMethodCall(node));
}
IIndex matchedIndex = null;
int[] mapping = null;
foreach (IIndex index in table.Indexes)
{
if (KeyExpressionHelper.TryGetMemberMapping(
index.KeyInfo.EntityKeyMembers,
keyMembers,
out mapping))
{
matchedIndex = index;
break;
}
}
if (matchedIndex == null)
{
// No matched index was found
return(base.VisitMethodCall(node));
}
var indexServices = GetKeyInfoHelper(matchedIndex.KeyInfo);
if (indexServices == null)
{
return(base.VisitMethodCall(node));
}
// Create key converter
ParameterExpression keyConverterParam = Expression.Parameter(keyType, "x");
LambdaExpression keyConverter =
Expression.Lambda(
KeyExpressionHelper.CreateKeyConversionExpression(keyConverterParam, matchedIndex.KeyInfo.EntityKeyMembers, mapping, helper, indexServices),
keyConverterParam);
// Create key emptyness detector
ParameterExpression keyEmptinessDetectorParam = Expression.Parameter(keyType, "x");
LambdaExpression keyEmptinessDetector =
Expression.Lambda(
KeyExpressionHelper.CreateKeyEmptinessDetector(
keyEmptinessDetectorParam,
helper),
keyEmptinessDetectorParam);
Type[] generics = node.Method.GetGenericArguments();
// GroupJoinIndexed call
MethodInfo indexedMethod = this.Indexed
.MakeGenericMethod(
generics[0],
generics[1],
generics[2],
matchedIndex.KeyInfo.KeyType,
generics[3]);
Expression indexedCall =
Expression.Call(
node.Object,
indexedMethod,
this.Visit(node.Arguments[0]),
Expression.Constant(matchedIndex),
ExpressionHelper.SkipQuoteNode(node.Arguments[2]),
keyEmptinessDetector,
keyConverter,
ExpressionHelper.SkipQuoteNode(node.Arguments[4]));
Type elementType = ReflectionHelper.GetElementType(indexedCall.Type);
// AsQueryable call
return(Expression.Call(
null,
QueryMethods.AsQueryable.MakeGenericMethod(elementType),
indexedCall));
}
public GenericKeyComparer(SortOrder[] sortOrders, IKeyInfoHelper helper)
{
if (helper == null)
{
throw new ArgumentNullException("helper");
}
int memberCount = helper.GetMemberCount();
if (memberCount <= 0)
{
throw new ArgumentException(
ExceptionMessages.InvalidKeyInfoHelper,
"helper");
}
if (sortOrders == null)
{
sortOrders = Enumerable.Repeat(SortOrder.Ascending, memberCount).ToArray();
}
if (sortOrders.Length != memberCount)
{
throw new ArgumentException(
ExceptionMessages.MemberAndSortOrderCountMismatch,
"sortOrders");
}
ParameterExpression x = Expression.Parameter(typeof(T), "x");
ParameterExpression y = Expression.Parameter(typeof(T), "y");
ParameterExpression variable = Expression.Variable(typeof(int), "var");
List <Expression> blockBody = new List <Expression>();
for (int i = 0; i < memberCount; i++)
{
Expression xMember = helper.CreateKeyMemberSelectorExpression(x, i);
Expression yMember = helper.CreateKeyMemberSelectorExpression(y, i);
Expression expr =
Expression.Assign(
variable,
this.CreateComparsion(xMember, yMember, sortOrders[i]));
if (0 < i)
{
expr =
Expression.IfThen(
Expression.Equal(variable, Expression.Constant(0)),
expr);
}
blockBody.Add(expr);
}
// Eval the last variable
blockBody.Add(variable);
var lambda = Expression.Lambda <Func <T, T, int> >(
Expression.Block(
new ParameterExpression[] { variable },
blockBody),
x,
y);
this.comparer = lambda.Compile();
}
