Declare tableadpaters globally on a page or keep them inside event handlers?

IceThatJaw · June 8th, 2012, 08:03 PM

I am having a hard time finding an answer to this on the web. If I am using the same Table Adapter in multiple events on a page is it better to just declare it once at the top of the page?

Performance wise, is there a difference?

Thanks.

Imar · June 9th, 2012, 05:03 AM

Hi there,

Yes, if they contain the same data, you should declare one outside all your methods and then fill it once. Where you do that depends; can be with a helper method that is called by each event handler, or you can do it in Page_Load or in the first event that fires.

Why are you using TableAdapters? Is that a deliberate design choice? They are more or less considered out-dated in .NET 4 applications....

Cheers,

Imar

IceThatJaw · June 10th, 2012, 01:01 PM

Quote:

Originally Posted by Imar

Hi there,

Yes, if they contain the same data, you should declare one outside all your methods and then fill it once. Where you do that depends; can be with a helper method that is called by each event handler, or you can do it in Page_Load or in the first event that fires.

Why are you using TableAdapters? Is that a deliberate design choice? They are more or less considered out-dated in .NET 4 applications....

Cheers,

Imar

Yea, I know TableAdpaters are obsolete but they are just so easy to use that I am using them for this site. Their downfalls are definitely apparent if I make changes to the database schema, that's for sure.

However, I am not proficient at LINQ but my SQL is pretty good so I like how you can just create query methods for each TableAdapter quickly just by using SQL queries. I also like how you can create partial classes of the TableAdapters to add business logic into the methods.

With the Entity Framework, if you want to group queries together with your tables is their any other way to do it other then hand coding classes for each table using LINQ in each method? Basically other then hand coding a the entire DAL yourself?

Not that it's a bad thing, it's just something that is very new to me.

Imar · June 11th, 2012, 04:25 AM

Quote:

With the Entity Framework, if you want to group queries together with your tables is their any other way to do it other then hand coding classes for each table using LINQ in each method? Basically other then hand coding a the entire DAL yourself?

Absolutely. You can create queries that JOINs two or more tables or get related entities. Depending on the data you need you then query complete entities or you can use anonymous objects. In the latter case, you can't return them from a method so you either need to create a class that serves as a ViewModel (which simply copies over your data into an object that doesn't do more than just hold data for transport) or return full entities.

If you can describe your scenarios in more detail, I might be able to supply a better answer and code example.

Cheers,

Imar