When Add Object() is called, a temporary Entity Key is generated and the Entity State is set to 'Added', as shown below: When context.Save Changes() is called, EF 4.0 goes ahead and inserts the record into the database.Your first check needs to be If there are no errors and the code runs then there is something wrong with the SQL statement.Most likely cause is that the @ID you pass in isn't found and so nothing can be updated.Likewise, the parameter values in the Astute readers will notice the similarity between the Access Data Source and Sql Data Source controls' inserting, deleting, and updating workflows.
NET 2.0 introduces three new data Web controls: the Grid View, the Details View, and the Form View.AND Primary Key Column Name N = @Primary Key Value To Update N , in this instance - has its value specified via the data source control's Select Parameters, which can specify a source for the parameter value.The source may be: a hard-coded value like "3.95", which would return all products less than .95; the value of a Web control on the page, allowing the user to enter a price bound in a Text Box; from the querystring; from session state; and so on. NET 2.0 introduced a number of new Web controls designed for accessing and modifying data. NET 2.0's data source controls make it possible to retrieve, insert, update, and delete data without having to write the tedious dedata access code that was so commonplace in ASP. Previous installments of this article series have looked at returning, inserting, and deleting data using the Sql Data Source control. These controls can work in unison with the data source controls to facilitate inserting, updating, and deleting data.These controls allow page developers to declaratively access and modify data without writing any code to perform the data access. In this article we will examine basics of using the Sql Data Source and Grid View controls to update records from a database.In a previous article, we saw how to Create an Entity Framework Model and Use it in Multiple Projects.