VB linq to sql isnull

2018-06-15 02:15:31

I want make this in linq to sql

select isnull(x.COD, '1') as 'NCOD'
from table x

I have tried this.

From x In table
select NCOD = x.COD ?? '1';

I'm using LINQPad 4 and VB Expression. but LINQPAd says that I can't use ? expression (No se puede usar aquí el carácter '?' in Spanish)

Any idea?

PD: sorry for my English.

If your value type is string, you can use following expression:

result = from x in values select IF(String.IsNullOrEmpty(x),"No value",x);

If it is a nullable type (like int?, Double?, SomeClass?):

result = from x in values select IF(x.HasValue,x,1);

Ref:

Nullable types in VB.NET - http://visualbasic.about.com/od/usingvbnet/a/nullabletypes.htm

Warning about VB IF operator: https://stackoverflow.com/a/11990998/1732138

Try the following query, this will be helpful to you.

var InvoiceNo = dbContext.table.where(x => (int?)x.ICOD) ?? "NCOD";

Here, ?? works only on nullable int int?

And you are a vb.net user than you should use following code, this will be help ful to you...

Dim InvoiceNo = If(dbContext.table.where(Function(x) DirectCast(x.ICOD, System.Nullable(Of Integer))), "NCOD")

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