实体框架 - 如何获取列? [英] Entity Framework - how do I get the columns?

问题描述

我希望获得列名称、类型以及该列是否是实体框架中表对象的 PK 的列表.

I wish to get a list of columns names, types and whether the column is a PK of a table object in Entity Framework.

我如何在 C# (4.0) 中执行此操作(理想情况下是通用的)?

How do I do this in C# (4.0) (ideally generically)?

获胜的答案将是有效且最重要的是通用的答案.

The winning answer will be one that does it efficiently and most importantly generically.

推荐答案

明白了 - 我使用了基于 linq 的反射查询:

Got it - I used a linq based reflection query:

IEnumerable<FieldList> properties = from p in typeof(T).GetProperties()
                                    where (from a in p.GetCustomAttributes(false)
                                    where a is EdmScalarPropertyAttribute   
                                    select true).FirstOrDefault()

排序！谢谢大家的建议.

Sorted! Thanks for the suggestions all.

仅供参考 - 我正在使用 LINQ 创建一个动态 where 子句，动态 lambda 表达式来构建例如search 默认情况下会自动搜索所有列.但我还需要验证列名，因为我将允许覆盖它，并且这些调用将通过 javascript ajax post 完成，其输入不可信 - 因此需要验证列名.

FYI - I am creating a dynamic where clause using LINQ, dynamic lambda expressions to build e.g. search which will automatically search through all columns by default. But I also needed the column names to verify because I will allow this to be overridden and these calls will be done via javascript ajax post whose input cannot be trusted - so needed to verify the column names.

我使用上面的方法将结果放入一个自定义对象中，该对象具有名为 FieldName、FieldType、PrimaryKey 的属性.呸.

I used the above to place the results into a custom object with properties called FieldName, FieldType, PrimaryKey. Ta daaa.

使用

IEnumerable<FieldList> properties = from p in typeof(T).GetProperties()
                                    where (from a in p.GetCustomAttributes(false)
                                    where a is EdmScalarPropertyAttribute
                                    select true).FirstOrDefault()
                                    select new FieldList
                                    {
                                       FieldName = p.Name,
                                       FieldType = p.PropertyType,
                                       FieldPK = p.GetCustomAttributes(false).Where(a => a is EdmScalarPropertyAttribute && ((EdmScalarPropertyAttribute)a).EntityKeyProperty).Count() > 0
                                     };    

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