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  • UnitOfWork 更新实体出错解决办法

    用UnitOfWork进行实体更新的时候,再查询实体一次,再去更新的时候会报如下错误:

    Attaching an entity of type 'TinyFrame.Data.DomainModel.t_user_application' failed because another entity of the same type already has the same primary key value. This can happen when using the 'Attach' method or setting the state of an entity to 'Unchanged' or 'Modified' if any entities in the graph have conflicting key values. This may be because some entities are new and have not yet received database-generated key values. In this case use the 'Add' method or the 'Added' entity state to track the graph and then set the state of non-new entities to 'Unchanged' or 'Modified' as appropriate.

    解决办法如下:

        public virtual async Task<T> GetOne(Expression<Func<T,bool>> where) {
                return await _dbSet.Where(where).AsNoTracking().FirstOrDefaultAsync();
            }

    用AsNoTracking不进行跟踪,就可以更新了

    记录下

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  • 原文地址:https://www.cnblogs.com/flyfish2012/p/3964198.html
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