private DbUnitTypeExpression SelectManyTranslate(TranslationContext context, MethodCallExpression exp)
{
var source = UnitTypeTranslate(context, exp.Arguments[0]);
var target = context.Lambda <DbUnitTypeExpression>(delegate(Expression body)
{
return(UnitTypeTranslate(context, body));
}, exp.Arguments[1], source.Item);
var item = context.Lambda <DbUnitItemTypeExpression>(delegate(Expression body)
{
return(UnitItemTypeTranslate(context, body) as DbUnitItemTypeExpression);
}, exp.Arguments[2], source.Item, target.Item);
if (item.ExpressionType == EExpressionType.DataItem || item.ExpressionType == EExpressionType.GroupItem)
{
item = new DbUnitItemContentExpression(item);
}
return(new DbCrossJoinExpression(source, target, item));
}
private DbUnitTypeExpression SelectTranslate(TranslationContext context, MethodCallExpression exp)
{
var source = UnitTypeTranslate(context, exp.Arguments[0]);
return(context.Lambda <DbUnitTypeExpression>(delegate(Expression body)
{
var itemType = UnitItemTypeTranslate(context, body) as DbUnitItemTypeExpression;
switch (itemType.ExpressionType)
{
case EExpressionType.DataItem:
case EExpressionType.GroupItem:
itemType = new DbUnitItemContentExpression(itemType);
break;
case EExpressionType.Select:
//如果出现重复SELECT调用则自动合并
return ((DbSelectExpression)source).ReplaceItem(itemType);
}
return new DbSelectExpression(source, itemType);
}, exp.Arguments[1], source.Item));
}
private DbUnitTypeExpression GropuAndJoinTranslate(TranslationContext context, MethodCallExpression exp, bool isgroup)
{
var source = UnitTypeTranslate(context, exp.Arguments[0]);
var target = UnitTypeTranslate(context, exp.Arguments[1]);
var left = context.Lambda <DbExpression>(delegate(Expression body)
{
return(ExpressionTranslate(context, body));
}, exp.Arguments[2], source.Item);
var right = context.Lambda <DbExpression>(delegate(Expression body)
{
return(ExpressionTranslate(context, body));
}, exp.Arguments[3], target.Item);
var rightitem = isgroup ? (DbExpression) new DbGroupSetExpression(target) : target.Item;
var result = context.Lambda <DbUnitItemTypeExpression>(delegate(Expression body)
{
return(UnitItemTypeTranslate(context, body) as DbUnitItemTypeExpression);
}, exp.Arguments[4], source.Item, rightitem);
if (result.ExpressionType == EExpressionType.DataItem || result.ExpressionType == EExpressionType.GroupItem)
{
result = new DbUnitItemContentExpression(result);
}
if (isgroup)
{
var value = new DbGroupJoinExpression(source, target, left, right, result);
((DbGroupSetExpression)rightitem).Parent = value;
return(value);
}
else
{
return(new DbInnerJoinExpression(source, target, left, right, result));
}
}
