/// <summary>
/// 获取当前线程的数据上下文
/// </summary>
/// <returns>数据上下文</returns>
public static YhContext CurrentContext()
{
YhContext _nContext = CallContext.GetData("yhcontext") as YhContext;
if (_nContext == null)
{
_nContext = new YhContext();
CallContext.SetData("yhcontext", _nContext);
}
return(_nContext);
}
//
// GET: /Linq/
public ActionResult Index()
{
YhContext db = new YhContext();
#region 基本Linq
#endregion
//几个点
//JOIN
var result1 = from b in db.Blogs
join c in db.Categories on b.Category.Name equals c.Name
select new { b.ID, b.Publish, 栏目ID = c.ID };
var result16 = db.Blogs.Join(db.Categories, b => b.Category.ID, c => c.ID, (b, c) => new{ 类型 = c.Name, 博客名称 = b.Title }).ToList();
//分组 注意泛型
var result12 = db.Blogs.GroupBy(b => b.Category.Name).Select(a => new { aa = a.Select(bs => bs.Category.Name), count = a.Count() }).ToList();
var result13 = db.Blogs.GroupBy(b => b.Publish).Select(c => new { aa = c.Select(cs => cs.Publish) }).ToList();
var result15 = db.Blogs.GroupBy(b => b.Volume).Select(group => new { Content = group.Select(bs => bs) }).ToList();
var result14 = db.Blogs.GroupBy(b => b.Volume).Select(group => new { Title = group.Select(bs => bs.Title) }).ToList();
//聚合
var result123 = (from b in db.Blogs
select new { b.Category.Name }).Distinct();//.SUM.MAX...
string json1 = JsonConvert.SerializeObject(result1);
JArray jsArray = JArray.Parse(json1);
string jss = "";
// jsArray.ForEach(j => jss = jss+j.Value<string>()+"||");
return(Content(jss));
return(Json(result16, JsonRequestBehavior.AllowGet));
}
