/// <summary>
/// 使用命名参数查询,尽量不要使用此方法, 可能会一次性查询出大量的数据, 应该使用分页查询通用方法
/// SqlQuery(select * from article keywords like @p0, "%"+keywords+"%")
/// </summary>
/// <typeparam name="T">需要得到的类型, 查询哪张表(必须和表名称一致)</typeparam>
/// <param name="sql">查询语句,参照注释</param>
/// <param name="param">查询参数</param>
/// <returns></returns>
public static List <T> selectList <T>(string sql, params object[] param) where T : class, new()
{
using (WeiQingEntities db = new WeiQingEntities())
{
var set = db.Set <T>();
var list = set.SqlQuery(sql, param).ToList();
return(list);
}
}
/// <summary>
/// 使用泛型保存对象到数据库中, 类型参数可以是 基类, 参数model对象可以是 扩展类对象
/// </summary>
/// <typeparam name="T">基类</typeparam>
/// <param name="model">子类对象</param>
/// <returns></returns>
public static int insert <T>(T model) where T : class
{
using (WeiQingEntities db = new WeiQingEntities())
{
DbSet <T> set = db.Set <T>();
set.Add(model);
return(db.SaveChanges());
}
}
/// <summary>
/// 使用泛型删除数据库中的对象, 类型参数可以是 基类, 参数model对象可以是 扩展类对象
/// </summary>
/// <typeparam name="T">基类</typeparam>
/// <param name="model">可以是扩展类对象</param>
/// <returns></returns>
public static int delete <T>(T model) where T : class
{
using (WeiQingEntities db = new WeiQingEntities())
{
var ent = db.Entry(model);
ent.State = EntityState.Deleted;
return(db.SaveChanges());
}
}
/// <summary>
/// 查询所有数据, 慎用, 除非可以包装一次取出的数据是有限的, 例如分类名称
/// </summary>
/// <typeparam name="T"></typeparam>
/// <returns></returns>
public static List <T> selectAll <T>() where T : class, new()
{
string tableName = typeof(T).Name;
using (WeiQingEntities db = new WeiQingEntities())
{
var set = db.Set <T>();
var list = set.SqlQuery(string.Format("select * from `{0}`", tableName)).ToList();
return(list);
}
}
/// <summary>
/// 使用linq进行简单的泛型查询,一次最多只能得到一条记录
/// </summary>
/// <typeparam name="T">需要得到的类型, 查询哪张表(必须和表名称一致)</typeparam>
/// <param name="id">主键</param>
/// <returns></returns>
public static T select <T>(int id) where T : class, new()
{
string tableName = typeof(T).Name;
using (WeiQingEntities db = new WeiQingEntities())
{
var set = db.Set <T>();
var model = set.SqlQuery(string.Format("select * from `{0}` where id={1}", tableName, id)).FirstOrDefault();
return(model);
}
}
/// <summary>
/// 删除
/// </summary>
/// <param name="obj"></param>
/// <returns></returns>
public static int Delete(object obj)
{
int effect = -1;
using (WeiQingEntities con = new WeiQingEntities())
{
con.Database.Log = new Action <string>(q => Debug.WriteLine(q));
DbEntityEntry entry = con.Entry(obj);
entry.State = EntityState.Deleted;
effect = con.SaveChanges();
return(effect);
}
}
/// <summary>
/// 新增
/// </summary>
/// <param name="obj"></param>
/// <returns></returns>
public static int Insert(object obj)
{
Type t = obj.GetType();
int effect = -1;
using (WeiQingEntities con = new WeiQingEntities())
{
con.Database.Log = new Action <string>(q => Debug.WriteLine(q));
DbSet set = con.Set(t);
set.Add(obj);
effect = con.SaveChanges();
return(effect);
}
}
/// <summary>
/// 批量删除
/// </summary>
/// <param name="objs"></param>
/// <returns></returns>
public static int DeleteMany(IEnumerable <object> objs)
{
int effect = 0;
var et = objs.GetEnumerator();
if (et.MoveNext())
{
Type t = et.Current.GetType();
using (WeiQingEntities con = new WeiQingEntities())
{
con.Database.Log = new Action <string>(q => Debug.WriteLine(q));
foreach (var o in objs)
{
DbEntityEntry entry = con.Entry(o);
entry.State = EntityState.Deleted;
}
effect = con.SaveChanges();
}
}
return(effect);
}
/// <summary>
/// 批量新增
/// </summary>
/// <param name="objs"></param>
/// <returns></returns>
public static int InsertMany(IEnumerable <object> objs)
{
int effect = 0;
var et = objs.GetEnumerator();
if (et.MoveNext())
{
Type t = et.Current.GetType();
using (WeiQingEntities con = new WeiQingEntities())
{
con.Database.Log = new Action <string>(q => Debug.WriteLine(q));
DbSet set = con.Set(t);
foreach (var o in objs)
{
set.Add(o);
}
effect = con.SaveChanges();
}
}
return(effect);
}
