I am using this linq query for login
var login = context.Person_Login
.Where(c => c.Username == username && c.Password == password)
.DefaultIfEmpty(new Person_Login({Id = -1})
.First();
but in execution throw this exception:
An unhandled exception of type 'System.NotSupportedException' occurred in EntityFramework.SqlServer.dll
Additional information: Unable to create a constant value of type 'MyProject.MyModels.Person_Login'. Only primitive types or enumeration types are supported in this context.
The exception message is quite descriptive.
DefaultIfEmpty(new Person_Login({Id = -1})
is not supported in Linq to Entities.
You can use the following instead
var login = context.Person_Login
.FirstOrDefault(c => c.Username == username && c.Password == password)
?? new Person_Login {Id = -1};
Note that DefaultIfEmpty
method is used mainly for performing LINQ left outer joins.
try
var login = context.Person_Login
.Where(c => c.Username == username &&
c.Password ==password)
.FirstOrDefault();
login = (login != null) ? login : (new Person_Login({Id = -1}));
Try
var login = context.Person_Login
.Where(c => c.Username == username && c.Password == password)
.FirstOrDefault(new Person_Login({Id = -1});
var login = context.Person_Login
.Any(c => c.Username == username && c.Password == password) ?
context.Person_Login.First(c => c.Username == username && c.Password == password) :
new Person_Login({Id = -1});
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