• VS2012里面使用EF框架的增删改查和分页的方法


      public class BaseRepository<T> where T : class
        {
            //实例化EF框架
            DataModelContainer db = new DataModelContainer();

            //添加
            public T AddEntities(T entity)
            {
                db.Entry<T>(entity).State = EntityState.Added;
                db.SaveChanges();
                return entity;
            }

            //修改
            public bool UpdateEntities(T entity)
            {
                db.Set<T>().Attach(entity);
                db.Entry<T>(entity).State = EntityState.Modified;
                return db.SaveChanges() > 0;
            }

            //修改
            public bool DeleteEntities(T entity)
            {
                db.Set<T>().Attach(entity);
                db.Entry<T>(entity).State = EntityState.Deleted;
                return db.SaveChanges() > 0;
            }

            //查询
            public IQueryable<T> LoadEntities(Func<T, bool> wherelambda)
            {
                return db.Set<T>().Where<T>(wherelambda).AsQueryable();
            }

            //分页
            public IQueryable<T> LoadPagerEntities<S>(int pageSize, int pageIndex, out int total,
                Func<T, bool> whereLambda, bool isAsc, Func<T, S> orderByLambda)
            {
                var tempData = db.Set<T>().Where<T>(whereLambda);

                total = tempData.Count();

                //排序获取当前页的数据
                if (isAsc)
                {
                    tempData = tempData.OrderBy<T, S>(orderByLambda).
                          Skip<T>(pageSize * (pageIndex - 1)).
                          Take<T>(pageSize).AsQueryable();
                }
                else
                {
                    tempData = tempData.OrderByDescending<T, S>(orderByLambda).
                         Skip<T>(pageSize * (pageIndex - 1)).
                         Take<T>(pageSize).AsQueryable();
                }
                return tempData.AsQueryable();
            }
        }

  • 相关阅读:
    zookeeper高可用集群搭建
    linux安装配置zookeeper-3.4.10
    hadoop小结
    YARN集群的mapreduce测试(六)
    YARN集群的mapreduce测试(五)
    YARN集群的mapreduce测试(四)
    mxnet卷积神经网络训练MNIST数据集测试
    人脸识别的损失函数
    完全图解RNN、RNN变体、Seq2Seq、Attention机制
    机器学习中的线性和非线性判断
  • 原文地址:https://www.cnblogs.com/sky-net/p/4331107.html
Copyright © 2020-2023  润新知