并且，与或者：&&与||

clist = clist.Where(r => r.Price > 50 && r.Price < 60 || r.Price < 30).ToList();

包含：contains

List
     
       clist= new cardata().SelectAll().Where(r => r.Name.Contains(TextBox1.Text)).ToList();
     

 等于：==

clist = clist.Where(r => r.Price==40).ToList();

clist = clist.Where(r => r.Price.Equals(40)).ToList();

 以。。开始、以。。结束

List
     
       ulist = con.users.Where(r => r.username.StartsWith("s")).ToList();            List
      
        ulsit = con.users.Where(r => r.username.EndsWith("t")).ToList();
      
     

最大值、最小值、平均值、求和

int s = con.users.Max(r=>r.ids);            int t = con.users.Min(r=>r.ids);            double h = con.users.Average(r => r.ids);            int d = con.users.Sum(r => r.ids);

求交集

List
     
       ulist1 = new List
      
       ();            List
       
         ulist2 = new List
        
         ();            List
         
           ulist3 = new List
          
           (); List
           
             ulist = ulist1.Intersect(ulist2).Intersect(ulist3).ToList();
           
          
         
        
       
      
     

顺序、倒序

List
     
       ulist = con.users.OrderBy(r => r.ids).ToList();            List
      
        ulist1 = con.users.OrderByDescending(r => r.ids).ToList();