如何在 LINQ WHERE 语句中使用 OR 运算符

Question

I just need an equivalent of this TSQL statement written in LINQ. Preferably in lambda statement but anything will work. TSQL statement:

select *
from Table1 as t1
where t1.Column1 = a OR t1.Column2 = b

Answer 1

Just like other C# code use || for OR

Method Syntax:

var query = db.Table1
              .Where(r=> r.Column1 == a || r.Column2 == b);

Query Syntax:

var query = from r in db.Table1
            where r.Column1 == a || r.Column2 == b
            select r;

Query Syntax compiles into Method syntax.

See: Query Syntax and Method Syntax in LINQ (C#)

Most queries in the introductory Language Integrated Query (LINQ) documentation are written by using the LINQ declarative query syntax. However, the query syntax must be translated into method calls for the .NET common language runtime (CLR) when the code is compiled.

You should see: Basic LINQ Query Operations (C#)

Answer 2

this work for me.

IQueryable noveltydata = (IQueryable)noveltyOfPeriod;

var fillNoveltyData = noveltydata. Where(c => c.TypeDay != 2 || c.TypeDay == 8). Where(c => c.EmployeeID == employeeID);

int DayNoSalary = (int)(from dataQueryVal in fillNoveltyData select dataQueryVal).Sum(e => e.Days);