1

我认为枚举可能是要走的路，并且根据操作（创建、删除）它会替换字符？然后我必须为“--”、“++”、“>=”和“>”hrrmm 存储一个变量。任何简单的建议都会很棒，我可以将其用作将来如何解决此类问题的参考！

public void ArrangeCategoriesOrderOnCreate(Category category)
{
    var tx = _session.BeginTransaction();
    var categories = _session.QueryOver<Category>()
        .Where(c => c.Parent.Id == category.Parent.Id && c.OrderInList >= category.OrderInList) // the >= category.OrderInList here
        .List<Category>();

    foreach(var item in categories)
    {
        item.OrderInList++; // The ++ here.
        _session.SaveOrUpdate(item);
    }
    tx.Commit();
}

public void ArrangeCategoriesOrderOnDelete(Category category)
{
    var tx = _session.BeginTransaction();
    var categories = _session.QueryOver<Category>()
        .Where(c => c.Parent.Id == category.Parent.Id && c.OrderInList > category.OrderInList) // the > category.OrderInList here
        .List<Category>();

    foreach(var item in categories)
    {
        item.OrderInList--; // the -- here.
        _session.SaveOrUpdate(item);
    }
    tx.Commit();
}

编辑 1

无法从 Invoke 确定成员类型，Invoke(value(CumbriaMD.Infrastructure.DataServices.CategoryDataServices+<> c_DisplayClass8).orderComparer, c.OrderInList, value(CumbriaMD.Infrastructure.DataServices.CategoryDataServices+<>c _DisplayClass8).category.OrderInList) , System.Linq.Expressions.InvocationExpression

痕迹：

[异常：无法从 Invoke 确定成员类型，Invoke(value(CumbriaMD.Infrastructure.DataServices.CategoryDataServices+<>c_ DisplayClass8).orderComparer, c.OrderInList, value(CumbriaMD.Infrastructure.DataServices.CategoryDataServices+<>c_DisplayClass8).category.OrderInList), System.Linq.Expressions.InvocationExpression] NHibernate.Impl.ExpressionProcessor.ProcessBooleanExpression(表达式表达式) +1113 NHibernate.Impl.ExpressionProcessor.ProcessExpression(表达式表达式) +114 NHibernate.Impl.ExpressionProcessor.ProcessAndExpression( BinaryExpression 表达式）+85 NHibernate.Impl.ExpressionProcessor.ProcessBinaryExpression（BinaryExpression 表达式）+124 NHibernate.Impl.ExpressionProcessor.ProcessExpression（表达式表达式）+95 NHibernate.Impl.ExpressionProcessor.ProcessLambdaExpression（LambdaExpression 表达式）+52 NHibernate.Impl.ExpressionProcessor。 ProcessExpression（表达式1 expression) +39 NHibernate.Criterion.QueryOver2.Add （表达式 2.Where（1 expression) +107 NHibernate.Criterion.QueryOver表达式1 expression) +42 NHibernate.Criterion.QueryOver2.NHibernate.IQueryOver.Where（表达式`1 表达式）+42

4

1 回答 1

2

一种简单的开始方法是使用 aFunc来区分常用功能并消除大部分重复。

public void ArrangeCategoriesOrderOnCreate(Category category)
{
    ArrangeCategoriesOrderOnAction(category, (a,b) => a>=b, x => x + 1);
}

public void ArrangeCategoriesOrderOnDelete(Category category)
{
    ArrangeCategoriesOrderOnAction(category, (a,b) => a>b, x => x - 1);
}

public void ArrangeCategoriesOrderOnAction(Category category, 
                               Expression<Func<int, int, bool>> orderComparer,
                               Func<int, int> orderUpdateCalculator)
{
    var tx = _session.BeginTransaction();
    var categories = _session.QueryOver<Category>()
        .Where(c => c.Parent.Id == category.Parent.Id 
               && orderComparer(c.OrderInList, category.OrderInList))
        .List<Category>();

    foreach (var item in categories)
    {
        item.OrderInList = orderUpdateCalculator(item.OrderInList);
        _session.SaveOrUpdate(item);
    }
    tx.Commit();
}
于 2012-08-11T06:23:56.960 回答