How to Fix the 'ObjectContext Instance...Disposed' Error in Entity Framework When Using GridViews?

Entity Framework Solution "ObjectContext instance has been released ..." Error

When using Entity Framework to fill GridView, the following errors may be encountered: "ObjectContext instance has been released, and it can no longer be used for connecting operations." This exception is due to the delayed loading of the Entity Framework, causing the navigation attributes to be marked marked For virtual attributes.

In the code provided, when the error appears in the

Loanproductname

column of GridView, the column is associated with the Loanproduct attribute loaded loaded. To solve this problem, you can use eager loading to pre -load related data. Use eagerly loading to repair the error

By speculating urgently loading, you can force Entity Framework and the main entities to retrieve the associated entities together. In this example, you can modify the query as follows:

This line ensures that each

Memberloan

<code>IQueryable<memberloan> query = db.MemberLoans.Include(m => m.LoanProduct);</code>

pre -load

Loanproduct Properties. Therefore, when you visit the Loanproductname column in GridView, the required data will be available immediately and the error will be eliminated. Other descriptions

Delay loading and urgent loading: Delay loading is optimized by loading related data only when required, and all relevant data are loaded at one time.

Virtual attributes:
• Virtual attributes allow Entity Framework to be delayed by covering navigation attributes and providing access to the underlying context. DBContext Release:
Using
• using Blocks can ensure that it is no longer needed to release it when it is no longer needed. This is a good practice of resource management. However, if the attribute of delay loading is still in use, the release will be triggered.
Release range:
• The context release range should cover all operations that need to be connected to the database.

The above is the detailed content of How to Fix the 'ObjectContext Instance...Disposed' Error in Entity Framework When Using GridViews?. For more information, please follow other related articles on the PHP Chinese website!