/// <summary>
/// EF DAL CURD基类
/// </summary>
/// <typeparam name="T"></typeparam>
public class BaseDAL<T> where T : class, new()
{
/// <summary>
/// 上下文网关
/// </summary>
protected SchoolEntities db = new SchoolEntities();
#region 1.Add
/// <summary>
/// 增加一条数据
/// </summary>
/// <param name="entity"></param>
/// <returns></returns>
public T AddEntity(T entity)
{
db.Entry<T>(entity).State = EntityState.Added;
// db.Set<T>().Add(entity);此方法同上方法
db.SaveChanges();
return entity;//因为可能要返回自动增长的ID，所以把整个实体返回，否则可以直接返回bool。
}
/// <summary>
/// 同时增加多条数据到一张表（事务处理）
/// </summary>
/// <param name="entitys"></param>
/// <returns></returns>
public bool AddEntity(List<T> entitys)
{
foreach (var entity in entitys)
{
db.Entry<T>(entity).State = EntityState.Added;
}
// entitys.ForEach(c=>db.Entry<T>(c).State = EntityState.Added);//等价于上面的循环
return db.SaveChanges() > 0;
}
#endregion
#region 2.Modify
/// <summary>
/// 修改一条数据，会修改所有列的值，没有赋值的属性将会被赋予属性类型的默认值**************
/// </summary>
/// <param name="entity"></param>
/// <returns></returns>
public bool ModifyEntity(T entity)
{
db.Set<T>().Attach(entity);
db.Entry<T>(entity).State = EntityState.Modified;//将所有属性标记为修改状态
return db.SaveChanges() > 0;
}
/// <summary>
/// 修改一条数据,会修改指定列的值
/// </summary>
/// <param name="entity">要修改的实体对象</param>
/// <param name="proNames">要修改的属性名称</param>
/// <returns></returns>
public bool ModifyEntity(T entity, params string[] proNames)
{
db.Set<T>().Attach(entity);
DbEntityEntry<T> dbee = db.Entry<T>(entity);
dbee.State = EntityState.Unchanged;//先将所有属性状态标记为未修改
proNames.ToList().ForEach(c => dbee.Property(c).IsModified = true);//将要修改的属性状态标记为修改
return db.SaveChanges() > 0;
}
/// <summary>
/// 根据条件批量修改指定的列********************
/// </summary>
/// <param name="entity"></param>
/// <param name="whereLambds"></param>
/// <param name="proNames"></param>
/// <returns></returns>
public bool ModifyEntity(T entity, Func<T, bool> whereLambds, params string[] proNames)
{
var entitys = db.Set<T>().Where(whereLambds).ToList();
PropertyInfo[] proinfos = entity.GetType().GetProperties();
List<PropertyInfo> list = new List<PropertyInfo>();
foreach (var p in proinfos)
{
if (proNames.Contains(p.Name))
{
list.Add(p);
}
}
entitys.ForEach(c => {
foreach (var p in list)
{
object value = p.GetValue(entity, null);
p.SetValue(c, value, null);
}
});
return db.SaveChanges() > 0;
}
#endregion
#region 3.Delete
/// <summary>
/// 删除一个实体对象
/// </summary>
/// <param name="entity"></param>
/// <returns></returns>
public bool DeleteEntity(T entity)
{
db.Set<T>().Attach(entity);
db.Entry<T>(entity).State = EntityState.Deleted;
return db.SaveChanges() > 0;
}
/// <summary>
/// 根据条件批量删除实体对象
/// </summary>
/// <param name="whereLambds"></param>
/// <returns></returns>
public bool DeleteEntityByWhere(Func<T, bool> whereLambds)
{
var data = db.Set<T>().Where<T>(whereLambds).ToList();
return DeleteEntitys(data);
}
/// <summary>
/// 事务批量删除实体对象
/// </summary>
/// <param name="entitys"></param>
/// <returns></returns>
public bool DeleteEntitys(List<T> entitys)
{
foreach (var item in entitys)
{
db.Set<T>().Attach(item);
db.Entry<T>(item).State = EntityState.Deleted;
}
return db.SaveChanges() > 0;
}
#endregion
#region 4.Select
//带条件查询
public IList<T> GetEntitys(Func<T, bool> whereLambds)
{
return db.Set<T>().Where<T>(whereLambds).ToList<T>();
}
//带排序查询
public IList<T> GetEntitys<S>(Func<T, bool> whereLambds, bool isAsc, Func<T, S> orderByLambds)
{
var temp = db.Set<T>().Where<T>(whereLambds);
if (isAsc)
{
return temp.OrderBy<T, S>(orderByLambds).ToList<T>();
}
else
{
return temp.OrderByDescending<T, S>(orderByLambds).ToList<T>();
}
}
//带分页查询
public IList<T> GetPagedEntitys<S>(int pageIndex, int pageSize, out int rows, out int totalPage, Func<T, bool> whereLambds, bool isAsc, Func<T, S> orderByLambds)
{
var temp = db.Set<T>().Where<T>(whereLambds);
rows = temp.Count();
if (rows % pageSize == 0)
{
totalPage = rows / pageSize;
}
else
{
totalPage = rows / pageSize + 1;
}
if (isAsc)
{
temp = temp.OrderBy<T, S>(orderByLambds);
}
else
{
temp = temp.OrderByDescending<T, S>(orderByLambds);
}
temp = temp.Skip<T>(pageSize* (pageIndex - 1)).Take<T>(pageSize);
return temp.ToList<T>();
}
//传统sql结合EF分页实现查询
public IList<T> GetPagedEntitys(int pageIndex, int pageSize, out int rows, out int totalPage, string sql, string where, bool isAsc, string orderKey)
{
sql = sql + " where 1=1 " + where;
sql += " order by " + orderKey;
if (!isAsc)
{
sql += " desc";
}
var temp = db.Database.SqlQuery<T>(sql);
rows = temp.Count();
if (rows % pageSize == 0)
{
totalPage = rows / pageSize;
}
else
{
totalPage = rows / pageSize + 1;
}
temp = temp.Skip(pageSize* (pageIndex - 1)).Take(pageSize);
return temp.ToList<T>(); ;
}
#endregion
#region 5.显式Tran
/// <summary>
/// 显式执行事务
/// </summary>
/// <param name="dics"></param>
/// <returns></returns>
public int ExeTran(IDictionary<string, DbParameter[]> dics)
{
int result = 0;
DbConnection con = ((IObjectContextAdapter)db).ObjectContext.Connection;
using (DbTransaction tran = con.BeginTransaction())
{
try
{
//第一种，传统的执行事务的方法
//db.Database.ExecuteSqlCommand();
// db.Database.SqlQuery();
foreach (var dic in dics)
{
if (dic.Value != null)
{
result += db.Database.ExecuteSqlCommand(dic.Key, dic.Value);
}
else
{
result += db.Database.ExecuteSqlCommand(dic.Key, dic.Value);
}
}
//第二种，
// db.UserInfo.Add(entity);
//db.UserInfo.Attach(entity);
//db.
tran.Commit();
return result;
}
catch (Exception ex)
{
tran.Rollback();
throw ex;
}
finally
{
con.Close();
}
}
}
#endregion
}
