public override Expression VisitMemberAccess(MemberExpression m)
{
if (MetaPosition.AreSameMember(m.Member, this.association.ThisMember.Member))
{
Expression[] keyValues = GetKeyValues(this.Visit(m.Expression), this.association.ThisKey);
return(Translator.WhereClauseFromSourceAndKeys(this.otherSouce, this.association.OtherKey.ToArray <MetaDataMember>(), keyValues));
}
Expression expression = this.Visit(m.Expression);
if (expression == m.Expression)
{
return(m);
}
if (((expression.Type != m.Expression.Type) && (m.Member.Name == "Count")) && TypeSystem.IsSequenceType(expression.Type))
{
return(Expression.Call(typeof(Enumerable), "Count", new Type[] { TypeSystem.GetElementType(expression.Type) }, new Expression[] { expression }));
}
return(Expression.MakeMemberAccess(expression, m.Member));
}
internal static Expression WhereClauseFromSourceAndKeys(Expression source, MetaDataMember[] keyMembers, Expression[] keyValues)
{
Type elementType = TypeSystem.GetElementType(source.Type);
ParameterExpression expression = Expression.Parameter(elementType, "p");
Expression left = null;
for (int i = 0; i < keyMembers.Length; i++)
{
MetaDataMember member = keyMembers[i];
Expression expression3 = (elementType == member.Member.DeclaringType) ? ((Expression)expression) : ((Expression)Expression.Convert(expression, member.Member.DeclaringType));
Expression expression4 = (member.Member is FieldInfo) ? Expression.Field(expression3, (FieldInfo)member.Member) : Expression.Property(expression3, (PropertyInfo)member.Member);
Expression expression5 = keyValues[i];
if (expression5.Type != expression4.Type)
{
expression5 = Expression.Convert(expression5, expression4.Type);
}
Expression right = Expression.Equal(expression4, expression5);
left = (left != null) ? Expression.And(left, right) : right;
}
return(Expression.Call(typeof(Enumerable), "Where", new Type[] { expression.Type }, new Expression[] { source, Expression.Lambda(left, new ParameterExpression[] { expression }) }));
}
private static Type GetClrType(SqlNode node)
{
SqlTableValuedFunctionCall call = node as SqlTableValuedFunctionCall;
if (call != null)
{
return(call.RowType.Type);
}
SqlExpression expression = node as SqlExpression;
if (expression != null)
{
if (TypeSystem.IsSequenceType(expression.ClrType))
{
return(TypeSystem.GetElementType(expression.ClrType));
}
return(expression.ClrType);
}
SqlSelect select = node as SqlSelect;
if (select != null)
{
return(select.Selection.ClrType);
}
SqlTable table = node as SqlTable;
if (table != null)
{
return(table.RowType.Type);
}
SqlUnion union = node as SqlUnion;
if (union == null)
{
throw Error.UnexpectedNode(node.NodeType);
}
return(union.GetClrType());
}
