v1.0.0

CC.Yi.DAL/BaseDal.cs

@@ -0,0 +1,86 @@
+using CC.Yi.IDAL;
+using CC.Yi.Model;
+using Microsoft.EntityFrameworkCore;
+using System;
+using System.Linq;
+using System.Linq.Expressions;
+
+namespace CC.Yi.DAL
+{
+    public class BaseDal<T> : IBaseDal<T> where T : class, new()
+    {
+        public DataContext Db;
+        public BaseDal(DataContext _Db)
+        {
+            Db = _Db;
+        }
+        public IQueryable<T> GetEntities(Expression<Func<T, bool>> whereLambda)
+        {
+            return Db.Set<T>().Where(whereLambda).AsQueryable();
+        }
+
+        public int GetCount(Expression<Func<T, bool>> whereLambda) //统计数量
+        {
+            return Db.Set<T>().Where(whereLambda).Count();
+        }
+
+        public IQueryable<IGrouping<S, T>> GetGroup<S>(Expression<Func<T, bool>> whereLambda, Expression<Func<T, S>> groupByLambda) //分组
+        {
+            return Db.Set<T>().Where(whereLambda).GroupBy<T, S>(groupByLambda).AsQueryable();
+
+        }
+
+
+
+        public IQueryable<T> GetPageEntities<S>(int pageSize, int pageIndex, out int total, Expression<Func<T, bool>> whereLambda, Expression<Func<T, S>> orderByLambda, bool isAsc)
+        {
+            total = Db.Set<T>().Where(whereLambda).Count();
+            if (isAsc)
+            {
+                var pageData = Db.Set<T>().Where(whereLambda)
+                              .OrderBy<T, S>(orderByLambda)
+                              .Skip(pageSize * (pageIndex - 1))
+                              .Take(pageSize).AsQueryable();
+                return pageData;
+            }
+            else
+            {
+                var pageData = Db.Set<T>().Where(whereLambda)
+                                 .OrderByDescending<T, S>(orderByLambda)
+                                 .Skip(pageSize * (pageIndex - 1))
+                                 .Take(pageSize).AsQueryable();
+                return pageData;
+            }
+        }
+
+        public T Add(T entity)
+        {
+            Db.Set<T>().Add(entity);
+            //Db.SaveChanges();
+            return entity;
+        }
+
+        public bool Update(T entity)
+        {
+            //所有字段均修改
+            Db.Entry<T>(entity).State = EntityState.Modified;
+            //return Db.SaveChanges() > 0;
+            return true;
+        }
+
+
+        public bool Delete(T entity)
+        {
+            Db.Entry<T>(entity).State = EntityState.Deleted;
+            //return Db.SaveChanges() > 0;
+            return true;
+        }
+        public bool Detete(int id)
+        {
+            var entity = Db.Set<T>().Find(id);//根据id找到实体
+            Db.Set<T>().Remove(entity);//由于这里先Find找到了实体，所以这里可以用Remove标记该实体要移除（删除）。如果不是先Find到实体就需要用System.Data.Entity.EntityState.Deleted
+            return true;
+        }
+
+    }
+}