如何在LINQ中使用SQL IN运算符

Question

I want to use IN operator in LINQ. I have a SQL query like given below. How do i include the where criteria.

SQL Query

SELECT     ServiceId, ServiceName, Rate
FROM         Service
WHERE     (ServiceId IN (1, 2, 3, 4))

LINQ

string serviceId = "(1,2,3,4,5,6)";

try
{
    using (var context = new DBEntities())
    {
        var query = (from c in context.Service
                     where c.ServiceId == serviceIds     //ServiceId is the primary key
                     select new
                     {
                        serviceId = c.ServiceId,
                        serviceName = c.ServiceName,
                        rate = c.Rate

                     }).ToList();

        GridView1.DataSource = query.ToList();
        GridView1.DataBind();

    }
}
catch (Exception ex)
{
    throw ex;
}

Answer 1

You could use contains of a list, make serviceId a list or array

var serviceIds = new int[] { 1, 2, 3, 4, 5, 6 };

try
{
    using (var context = new DBEntities())
    {
        var query = (from c in context.Service
                        where serviceIds.Contains(c.ServiceId)      //ServiceId is the primary key
                        select new
                        {
                            serviceId = c.ServiceId,
                            serviceName = c.ServiceName,
                            rate = c.Rate

                        }).ToList();

        GridView1.DataSource = query.ToList();
        GridView1.DataBind();

    }
}
catch (Exception ex)
{
    throw ex;
}

Answer 2

where serviceId.Contains(c.ServiceId)

Answer 3

I prefer to use Any, there may be some problems while using contains.

var serviceIds = new int[] { 1, 2, 3, 4, 5, 6 };

try
{
    using (var context = new DBEntities())
    {
        var query = (from c in context.Service
                        where serviceIds.Any(t=> t.ID == c.ServiceId)
                        select new
                        {
                            serviceId = c.ServiceId,
                            serviceName = c.ServiceName,
                            rate = c.Rate

                        }).ToList();

        GridView1.DataSource = query.ToList();
        GridView1.DataBind();

    }
}
catch (Exception ex)
{
    throw ex;
}