//查询列表SqlSugarClient db = SugarContext.GetInstance();List<teacher> tList = db.Queryable<teacher>().ToList();Console.WriteLine(tList.Count);var studentDynamic = db.Queryable<student>().ToDynamic();Console.WriteLine(studentDynamic);string teaJson = db.Queryable<teacher>().ToJson();Console.WriteLine(teaJson);//Json序列化的DateTime处理 db.SerializerDateFormat = "yyyy年MM月dd日";string teacher1 = db.Queryable<teacher>().OrderBy("tbirthday desc").Take(2).ToJson();string teacher2 = db.Sqlable().From<teacher>("t").SelectToJson(" top 1 *");string teacher3 = db.SqlQueryJson("select top 1 * from teacher;");Console.WriteLine(teacher1);Console.WriteLine(teacher2);Console.WriteLine(teacher3);Console.WriteLine(tList.First().tbirthday.Value.ToString("yyyy-MM-dd"));

           // string pattern = @"\\/Date\((\d+)\)\\/"; //源代码中的正则string pattern = @"\\/Date\((-*\d+)\)\\/"; //2016-11-22 修改正则

//查询单条
SqlSugarClient db = SugarContext.GetInstance();
teacher tea1 = db.Queryable<teacher>().Single(t => t.tno == "804");//如果查询数据库没有数据，抛出异常
Console.WriteLine(tea1.tname);
//根据主键查询单条
teacher tea2 = db.Queryable<teacher>().InSingle("814");//如果查询数据为空，返回null
Console.WriteLine(tea2.ToJsonString());// 输出：null
/***考虑查询为空的情况***/
teacher tea3 = db.Queryable<teacher>().SingleOrDefault(t => t.tno == "814");
Console.WriteLine(tea3.ToJsonString());// 输出：null
teacher tea4 = db.Queryable<teacher>().Where(q => q.tno == "814").FirstOrDefault(); //此处扩展方法仿EF First()/FirstOrDefault()
Console.WriteLine(tea4.ToJsonString()); // 输出：null/*****常用查询******/
//1.判断是否存在
bool exists1 = db.Queryable<teacher>().Any(q => q.tno == "814");
Console.WriteLine(exists1);
//2.模糊查询，含有
List<teacher> contains1 = db.Queryable<teacher>().Where(q => q.tname.Contains("李")).ToList();
Console.WriteLine(contains1.ToJsonString());
//以xxx结尾
List<teacher> end1 = db.Queryable<teacher>().Where(q => q.tname.EndsWith("成")).ToList();
Console.WriteLine(end1.ToJsonString());
//3. in关键词查询
string[] idList = new string[] { "804", "825" };
List<teacher> in1 = db.Queryable<teacher>().In(q => q.tno, idList)  //如果不支持拉姆达表达式，默认为主键
    .ToList();
Console.WriteLine(in1.ToJsonString());
List<teacher> in2 = db.Queryable<teacher>().Where(q => idList.Contains(q.tno)).ToList();
Console.WriteLine(in2.ToJsonString());/*********汇总查询等***********/
//1.获取总数
int count = db.Queryable<teacher>().Where(q => q.tsex == "男").Count();
Console.WriteLine("count=" + count);
//2.获取最大值
decimal maxDegree = db.Queryable<score>().Where(q => q.cno == "3-105").Max(q => q.degree) //此处Max返回的结果为Object需要拆箱
    .ObjToDecimal();
Console.WriteLine("maxDegree:" + maxDegree);
//3.获取最小值
decimal minDegree = db.Queryable<score>().Where(q => q.cno == "3-105").Min(q => q.degree).ObjToDecimal();
Console.WriteLine("minDegree:" + minDegree);
//4.平均值
//SqlSugar 不支持 平均值的扩展方法/***复杂的查询可以使用Sql字符串实现***/
//var list = db.Queryable<InsertTest>().Where("id=@id and name=@name", new { id = 1, name = xxx }).ToList();

//分页查询处理
SqlSugarClient db = SugarContext.GetInstance();
//分页方式1
Queryable<teacher> query = db.Queryable<teacher>();
query = query.Where(q => q.tno.StartsWith("8"));
//排序
//query = query.OrderBy("tbirthday desc"); //排序说明，如果是倒叙，需要传入排序的sql片段
query = query.OrderBy(q => q.tbirthday);    //如果是正序，可以指定拉姆达表达式
int allCount = query.Count();
//分页
//List<teacher> list1 = query.Skip(1).Take(2).ToList();
//或者
List<teacher> list1 = query.ToPageList(1, 2);
Console.WriteLine("list1-count:" + allCount);
Console.WriteLine("list1:" + list1.ToJsonString());//分页方式2+符合查询 多where是and拼接
Queryable<student> query2 = db.Queryable<student>();
query2 = query2.Where(q => q.ssex == "男");
query2 = query2.Where(q => q.sname.EndsWith("军"));
//排序
query2 = query2.OrderBy(q => q.sbirthday);
int allCount2 = 0;
//分页
List<student> list2 = query2.ToPageList(1, 2, ref allCount2);
Console.WriteLine("list2-count:" + allCount2);
Console.WriteLine("list2:" + list2.ToJsonString());

//分组，查询汇总
SqlSugarClient db = SugarContext.GetInstance();
dynamic result1 = db.Queryable<student>().GroupBy(q => q.ssex).Select("ssex,count(*) Count").ToDynamic();
foreach (var item in result1)
{Console.WriteLine(item.ssex + "----" + item.Count);
}string result2 = db.Queryable<score>().GroupBy(q => q.sno).Select("sno,isnull(sum(degree),0)").ToJson();
Console.WriteLine(result2);

static void QueryFive()
{//关联表查询，筛选等SqlSugarClient db = SugarContext.GetInstance();//将结果转换成其他对象var result = db.Queryable<score>().JoinTable<student>((s1, s2) => s1.sno == s2.sno).OrderBy(s1 => s1.degree).Take(1).Select<score, student, Score_Student>((s1, s2) => new Score_Student{sno = s1.sno,sname = s2.sname,cno = s1.cno,degree = s1.degree}).ToList();Console.WriteLine(result.ToJsonString());//输出结果//[{"sno":"101","sname":"李军","degree":64.0,"cno":"3-105"}]//关联查询//特别说明：如果指定了关联表代表参数s1,s2,那么在后边的筛选等操作中需要使用表字段的地方，必须使用s1或s2var result2 = db.Queryable<score>().JoinTable<student>((s1, s2) => s1.sno == s2.sno).Where(s1 => s1.degree > 64).Where(s1 => s1.degree < 70).ToJson();Console.WriteLine(result2);//输出结果：//[{"sno":"109","cno":"3-245","degree":68.0,//"sno1":"109","sname":"王芳","ssex":"女","sbirthday":"\/Date(161193600000)\/","class":"95031"}]//获取单个表的投影//特别说明，如果想获取单个表的投影，需要先将查询结果.ToList(),然后在创建匿名对象//或者 Select()中使用sql指定列名var result3 = db.Queryable<student>().OrderBy(q => q.sbirthday).Take(1).ToList().Select(q => new{sno = q.sno,sname = q.sname});Console.WriteLine(result3.ToJsonString());//输出结果：//[{"sno":"103","sname":"陆军"}]//获取多个表，投影var result4 = db.Queryable<score>().JoinTable<student>((s1, s2) => s1.sno == s2.sno).OrderBy(s1 => s1.degree).Take(1).Select("s1.*,s2.sname as sname").ToJson();Console.WriteLine(result4);//输出结果：//[{"sno":"101","cno":"3-105","degree":64.0,"sname":"李军","row_index":1}]
}
public class Score_Student
{public string sno { get; set; }public string sname { get; set; }public decimal degree { get; set; }public string cno { get; set; }
}