public QueryFragment WrapToFragment()
{
//if (this.Fragment.SelectPart == null)
//{
// this.Fragment.SelectPart = new List<Column>();
//}
if (this.Fragment.SelectPart.Count == 0)
{
var members = this.ExportType.GetProperties(BindingFlags.Public | BindingFlags.Instance);
var typeMapper = TypeMapperCache.GetTypeMapper(this.ExportType);
var tableName = GetTableAlias(this.ExportType);
for (var i = 0; i < members.Length; i++)
{
var member = members[i];
var tempColumn = this.GetMappedColumn(this.ExportType, member.Name);
if (tempColumn == null)
{
var columnMapper = typeMapper.AllMembers.SingleOrDefault(m => m.Name == member.Name);
this.Fragment.SelectPart.Add(new MemberColumn(columnMapper.ColumnName, tableName, member.Name)
{
Type = member.ReflectedType
});
}
else
{
tempColumn.Alias = member.Name;
this.Fragment.SelectPart.Add(tempColumn);
}
}
}
return(this.Fragment);
}
protected override Expression VisitConstant(ConstantExpression node)
{
if (node.Type.GetGenericTypeDefinition() == typeof(DataQuery <>))
{
var elementType = node.Type.GetGenericArguments()[0];
this.context.ExportType = this.context.ImportType = elementType;
var typeMapper = TypeMapperCache.GetTypeMapper(elementType);
this.context.Fragment.FromPart.Add(new SingleTable(typeMapper.TableName, this.context.GetTableAlias(elementType)));
}
return(node);
}
protected override Expression VisitMember(MemberExpression node)
{
if (node.Expression != null && node.Expression.IsParameter())
{
var parameterExpresion = node.Expression.GetParameterExpresion();
var memberType = node.Member.DeclaringType;
if (parameterExpresion != null && parameterExpresion.Type.IsSubclassOf(memberType))
{
// memberType = parameterExpresion.Type;
TypeMapperCache.AddTransferTypeMapper(memberType, parameterExpresion.Type);
}
if (node.Member.MemberType == MemberTypes.Property)
{
var property = node.Member as PropertyInfo;
if (property.PropertyType.IsGenericType && property.PropertyType.GetGenericTypeDefinition() == typeof(IEnumerable <>))
{
memberType = property.PropertyType.GenericTypeArguments.First();
this.Column = new MemberColumn("*", null, UseColumnAlias ? node.Member.Name : null)
{
Type = node.Type
};
return(node);
}
}
var tempColumn = this.Context.GetMappedColumn(memberType, node.Member.Name);
if (tempColumn == null)
{
var typeMapper = TypeMapperCache.GetTypeMapper(memberType);
var columnMapper = typeMapper.AllMembers.SingleOrDefault(m => m.Name == node.Member.Name);
this.Column = new MemberColumn(columnMapper.ColumnName, Context.GetTableAlias(TypeMapperCache.GetTransferTypeMapper(memberType)), UseColumnAlias ? node.Member.Name : null)
{
Type = node.Type
};
}
else
{
this.Column = tempColumn;
}
}
else
{
var objectMember = Expression.Convert(node, typeof(object));
var getterLambda = Expression.Lambda <Func <object> >(objectMember);
var getter = getterLambda.Compile()();
this.Column = new ParameterColumn(this.Context.AddParameter(getter))
{
Type = node.Type
};
}
return(node);
}
private static void InitialKeyOfParameter <T>(object parameter)
{
var type = typeof(T);
var typeMapper = TypeMapperCache.GetTypeMapper(type);
var seed = new Snowflake();
if (typeMapper.Name == TypeMapper.Dictionary_Name)
{
var diction = parameter as IDictionary;
foreach (var member in typeMapper.GetKeyMembers(false).Where(m => m.KeyType == KeyType.Snxowflake))
{
if (!diction.Contains(member.Name))
{
diction.Add(member.Name, seed.GenerateId());
}
else
{
diction[member.Name] = seed.GenerateId();
}
}
}
else
{
var instanceType = parameter.GetType();
foreach (var member in typeMapper.GetKeyMembers(false).Where(m => m.KeyType == KeyType.Snxowflake))
{
var property = instanceType.GetProperty(member.Name);
if (property == null)
{
//the property does not exist
return;
}
var setMethod = property.GetSetMethod();
if (setMethod == null)
{
//the property is readonly
return;
}
else
{
var instance = Expression.Constant(parameter);
var valueParameter = Expression.Parameter(property.PropertyType);
var method = Expression.Call(instance, setMethod, valueParameter);
var expression = Expression.Lambda <Action <long> >(method, valueParameter).Compile();
var nextValue = seed.GenerateId();
expression(nextValue);
}
}
}
}
protected override Expression VisitMethodCall(MethodCallExpression node)
{
switch (node.Method.Name)
{
case "First":
case "FirstOrDefault":
this.Visit(node.Arguments[0]);
if (this.context.IsQueryResultChanged)
{
var oldContext = this.context;
this.context = oldContext.CopyTo();
this.context.Fragment.FromPart.Add(new QueryTable(oldContext.WrapToFragment(), this.context.GetTableAlias(oldContext.ExportType)));
}
if (node.Arguments.Count == 2)
{
ParseWhereExpresson(node.Arguments[1]);
}
this.context.Fragment.Take = 1;
break;
case "Last":
case "LastOrDefault":
this.Visit(node.Arguments[0]);
if (this.context.IsQueryResultChanged)
{
var oldContext = this.context;
this.context = oldContext.CopyTo();
this.context.Fragment.FromPart.Add(new QueryTable(oldContext.WrapToFragment(), this.context.GetTableAlias(oldContext.ExportType)));
}
if (node.Arguments.Count == 2)
{
ParseWhereExpresson(node.Arguments[1]);
}
break;
case "Where":
this.Visit(node.Arguments[0]);
if (this.context.IsQueryResultChanged)
{
var oldContext = this.context;
this.context = oldContext.CopyTo();
this.context.Fragment.FromPart.Add(new QueryTable(oldContext.WrapToFragment(), this.context.GetTableAlias(oldContext.ExportType)));
}
ParseWhereExpresson(node.Arguments[1]);
break;
case "Select":
this.Visit(node.Arguments[0]);
var selectVisitor = new SelectExpressionVisitor(context);
selectVisitor.Visit(node.Arguments[1]);
this.context.Fragment.SelectPart = selectVisitor.Columns;
break;
case "Skip":
this.Visit(node.Arguments[0]);
this.context.Fragment.Skip = (int)(node.Arguments[1] as ConstantExpression).Value;
break;
case "Take":
this.Visit(node.Arguments[0]);
this.context.Fragment.Take = (int)(node.Arguments[1] as ConstantExpression).Value;
break;
case "OrderBy":
case "OrderByDescending":
case "ThenBy":
case "ThenByDescending":
this.Visit(node.Arguments[0]);
var orderVisitor = new MemberExpressionVisitor(context);
orderVisitor.Visit(node.Arguments[1]);
this.context.Fragment.OrderPart.Add(new OrderCondition(orderVisitor.Column,
node.Method.Name == "OrderBy" || node.Method.Name == "ThenBy" ? "asc" : "desc"));
break;
case "Any":
case "Count":
var parser = new QueryExpressionParser(this.connection, this.context.CopyTo());
parser.Visit(node.Arguments[0]);
this.context.Fragment.FromPart.Add(new QueryTable(parser.context.WrapToFragment(), this.context.GetTableAlias(parser.ExportType)));
if (node.Arguments.Count > 1)
{
ParseWhereExpresson(node.Arguments[1]);
}
this.context.Fragment.SelectPart.Add(new FunctionColumn()
{
Formatter = "Count(*)"
});
break;
case "GroupJoin":
ParseJoinExpression(node, JoinMode.LeftJoin);
break;
case "Join":
ParseJoinExpression(node, JoinMode.InnerJoin);
break;
case "SelectMany":
ParseSelectManyExpression(node);
break;
case "GroupBy":
ParseGroupByExpression(node);
break;
case "Predicate":
if (node.Arguments[0].Type == typeof(IDbConnection))
{
var elementType = node.Type.GetGenericArguments()[0];
this.context.ExportType = this.context.ImportType = elementType;
var typeMapper = TypeMapperCache.GetTypeMapper(elementType);
this.context.Fragment.FromPart.Add(new SingleTable(typeMapper.TableName, this.context.GetTableAlias(elementType)));
}
break;
case "DefaultIfEmpty":
break;
default:
break;
}
return(node);
}
