LINQ to Entites: How should I handle System.InvalidOperationException when checking for existance of

Posted by chris on Stack Overflow See other posts from Stack Overflow or by chris
Published on 2010-04-14T19:13:06Z Indexed on 2010/04/14 19:23 UTC
Read the original article Hit count: 182

Filed under:

linq-to-entities

|

exception-handling

I have a many-to-one relationship that users can edit via checkboxes. PK of Foo is ID, and fid contains the id from the checkbox.

I'm checking to see if an element exists with:

Foo ent;
try
{
  ent = ctx.Foo.First(f => f.ID == fid);
}
catch (System.InvalidOperationException ioe)
{
  ent = new Foo();
}

It seems to me that I should be able to do this without throwing an exception. What would be the best way to do this?

© Stack Overflow or respective owner

Related posts about linq-to-entities

HELP: deploying applications that use LINQ to Entities.

as seen on Stack Overflow - Search for 'Stack Overflow'
HI COMUNITY!!!! I want to use L2E since it s very convenient to my company's apps, I created a demo project, the demo does run on every machine but when I, lets say, press a button that has some code that uses the entity I get this error: specified store provider cannot be found in the configuration… >>> More
Linq to Entities : using ToLower() on NText fields

as seen on Stack Overflow - Search for 'Stack Overflow'
I'm using SQL Server 2005, with a case sensitive database.. In a search function, I need to create a Linq To Entities (L2E) query with a "where" clause that compare several strings with the data in the database with these rules : The comparison is a "Contains" mode, not strict compare : easy as… >>> More
LiNQ to Entities, Include less

as seen on Stack Overflow - Search for 'Stack Overflow'
Hi, If you are making a LinQ to entities expression for ClassA where A has a relation to ClassB like this: var temp = from p in myEntities.ClassA.Include("ClassB") where ... select p; You will get a set of ClassA:s with the reference to ClassB loaded. The thing in my case… >>> More
deploying applications that use LINQ to Entities.

as seen on Stack Overflow - Search for 'Stack Overflow'
HI COMUNITY!!!! I want to use L2E since it s very convenient to my company's apps, I created a demo project, the demo does run on every machine but when I, lets say, press a button that has some code that uses the entity I get this error: specified store provider cannot be found in the configuration… >>> More
LINQ To Entities - Items, ItemCategories & Tags

as seen on Stack Overflow - Search for 'Stack Overflow'
Hi There, I have an Entity Model that has Items, which can belong to one or more categories, and which can have one or more tags. I need to write a query that finds all tags for a given ItemCategory, preferably with a single call to the database, as this is going to get called fairly often. I currently… >>> More

Related posts about exception-handling

what is difference between Exception handling Application block & Exception handling

as seen on Stack Overflow - Search for 'Stack Overflow'
what is difference between Exception handling Application block & Exception handling in regular dot net classes ? i don't think it is beneficial to use of Exception handling Application block. What is exact use of that block ?? >>> More
Activation Error while testing Exception Handling Application Block

as seen on Stack Overflow - Search for 'Stack Overflow'
I'm getting the following error while testing my EHAB implementation: {"Activation error occured while trying to get instance of type ExceptionPolicyImpl, key "LogPolicy""} System.Exception Stack Trace: StackTrace " at Microsoft.Practices.ServiceLocation.ServiceLocatorImplBase.GetInstance(Type… >>> More
Delphi Exception handling problem with multiple Exception handling blocks

as seen on Stack Overflow - Search for 'Stack Overflow'
I'm using Delphi Pro 6 on Windows XP with FastMM 4.92 and the JEDI JVCL 3.0. Given the code below, I'm having the following problem: only the first exception handling block gets a valid instance of E. The other blocks match properly with the class of the Exception being raised, but E is unassigned… >>> More
Delph Exception handling problem with multiple Exception handling blocks

as seen on Stack Overflow - Search for 'Stack Overflow'
I'm using Delphi Pro 6 on Windows XP with FastMM 4.92 and the JEDI JVCL 3.0. Given the code below, I'm having the following problem: only the first exception handling block gets a valid instance of E. The other blocks match properly with the class of the Exception being raised, but E is unassigned… >>> More
Delphi Exception Handling - How to clean up properly?

as seen on Stack Overflow - Search for 'Stack Overflow'
I'm looking at some code in an application of ours and came across something a little odd from what I normally do. With exception handling and cleanup, we (as well as many other programmers out there, I'm sure) use a Try/Finally block embedded with a Try/Except block. Now I'm used to the Try/Except… >>> More