Because LINQ is lazily evaluated you can build up a query and never go to
the database (until you enumerate it anyway). So you can probably do
something like this:
var products = db.Products;
if(!showDiscontinued)
{
products = products.Where(x => x.IsDiscontinued == false);
}
// many more clauses and filters
// Up until now no database requests have been made
LinqDataSource.DataSource = products;
// When the LinqDataSource enumerates the products object the query will be
executed.
Michael M. Minutillo
Indiscriminate Information Sponge
http://codermike.com
On Fri, Mar 30, 2012 at 2:14 PM, Peter Maddin <[email protected]>wrote:
> Looks like the linqdatasource generates the linq for you. You just have to
> use the properties like select and where, before you bind the
> linqdatasource to your viewgrid.****
>
> ** **
>
> I feel like this sorts of defeats learning linq to some degree.****
>
> ** **
>
> *Regards Peter Maddin*
> *Applications Development Officer*
> *Path**West Laboratory Medicine WA*
> *Phone : +618 6396 4285 (Monday, Wednesday,Friday)*
>
> *Phone : +618 9346 4372 (Tuesday, Thursday)**
> Mobile: 0423 540 825*
> *E-Mail : [email protected]; [email protected]*
> *The contents of this e-mail transmission outside of the WAGHS network
> are intended solely for the named recipient's), may be confidential, and
> may be privileged or otherwise protected from disclosure in the public
> interest. The use, reproduction, disclosure or distribution of the contents
> of this e-mail transmission by any person other than the named recipient(s)
> is prohibited. If you are not a named recipient please notify the sender
> immediately**.*****
>
> ****
>
> ** **
>
> *From:* [email protected] [mailto:
> [email protected]] *On Behalf Of *Peter Maddin
> *Sent:* Friday, 30 March 2012 1:39 PM
> *To:* [email protected]
> *Subject:* Dynamically binding a linq query to a linqdatasource****
>
> ** **
>
> I want to use linqtosql to do crud.****
>
> ** **
>
> I want to bind a viewgrid to a linqdatasource which is bound to a
> datacontext.****
>
> ** **
>
> If you want to do this for every row in the table that is easy.****
>
> I want to dynamically build a linq query to return a subset of rows that I
> can manipulate and update within the viewgrid and then apply the changes
> back to the database.****
>
> ** **
>
> The linqdatasource requires a contexttypename and then a table name.****
>
> ** **
>
> Is it possible to build a dynamic linq query i.e. get all customers that
> are in Victoria and have a debt less than $1000 and bind this via the
> linqdatasource to my ViewGrid. I can then update records via the ViewGrid
> and then submit these back using the datacontext.****
>
> ** **
>
> I would seem this would be a fairly common requirement. All my information
> on LINQ requires me to wade through pages of how to dump stuff to the
> console or do really simple binding.****
>
> ** **
>
> *Regards Peter Maddin*
> *Applications Development Officer*
> *Path**West Laboratory Medicine WA*
> *Phone : +618 6396 4285 (Monday, Wednesday,Friday)*
>
> *Phone : +618 9346 4372 (Tuesday, Thursday)
> Mobile: 0423 540 825*
> *E-Mail : [email protected]; [email protected]*
> *The contents of this e-mail transmission outside of the WAGHS network
> are intended solely for the named recipient's), may be confidential, and
> may be privileged or otherwise protected from disclosure in the public
> interest. The use, reproduction, disclosure or distribution of the contents
> of this e-mail transmission by any person other than the named recipient(s)
> is prohibited. If you are not a named recipient please notify the sender
> immediately**.*****
>
> ****
>
> ** **
>
