LINQ巩固

Posted 2020-12-29 zzr-stdio

LINQ巩固

1. LINQ过滤运算符
   Where 基于谓词函数过滤值
   测试例子如下:

public class TestModel
{
    public string Name { get; set; }
    public string Age { get; set; }
}

 List<TestModel> lst = new List<TestModel>()
            {
                new TestModel(){Name = "张三" },
                new TestModel(){Name = "李四" },
            };
var querys1 = from item in lst where item.Name == "李四" select item;
var querys2 = lst.Where(item => item.Name == "李四");

1. LINQ Join操作

!运算符	描述	查询语法
Join	运算符连接两个序列配键的基础	join...in...on...equals...
GroupJoin	连接连个序列和组匹配元素	join...in...on...equals...into