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[shapper]

Hi,

In a Linq query I have the following:

where t.Name == tag

How can I make this line to have no effect if tag is empty?
In this moment if tag is empty I don't get any record.

tag is a string.

Thank You,
Miguel

 

[Chris Dunaway]

Hi,

In a Linq query I have the following:

where t.Name == tag

How can I make this line to have no effect if tag is empty?
In this moment if tag is empty I don't get any record.

tag is a string.

Thank You,
Miguel

What do you mean when you say, "tag is empty"? How is tag defined?
Is it of type System.Object? or is it a string?

You could try using something like:

where t.Name == tag || tag == null //Or whatever is appropriate
for an "empty" tag.

Not sure if this is what you need.

Chris

 

[shapper]

What do you mean when you say, "tag is empty"?  How is tag defined?
Is it of type System.Object? or is it a string?

You could try using something like:

where t.Name == tag || tag == null        //Or whatever is appropriate
for an "empty" tag.

Not sure if this is what you need.

Chris

The query is inside a function:
public ActionResult List(int? page, string tag) {

I think I could, for example, call List(null, "")

I am not sure if I can call List(null, null)

I tried to use:
public ActionResult List(int? page, string? tag)

But I get the error:
The type 'string' must be a non-nullable value type in order to use it
as parameter 'T' in the generic type or method 'System.Nullable<T>'

Thanks,
Miguel

 

[Chris Dunaway]

The query is inside a function:
public ActionResult List(int? page, string tag) {

I think I could, for example, call List(null, "")

I am not sure if I can call List(null, null)

I tried to use:
public ActionResult List(int? page, string? tag)

But I get the error:
The type 'string' must be a non-nullable value type in order to use it
as parameter 'T' in the generic type or method 'System.Nullable<T>'

Thanks,
Miguel

That's because string is already nullable, it makes no sense to
declare it as string?.

Chris