Updating data using linq
After clicking the Add button the Context Data file is created.Now we should drag all the tables onto the left-hand side of the designer and save (as shown in the following figure).NET Framework 3.5 release, and which enables you to easily model relational databases using . You can use LINQ expressions to query the database with them, as well as update/insert/delete data.Below are the first three parts of my LINQ to SQL series: In today's blog post I'll cover how we we can use the data model we created earlier, and use it to update, insert, and delete data.Today, in this tutorial, I will try to give some more examples on other types of database operations, that writes/updates the database.These will cover writing and executing ‘Update’/’Insert’/’Delete’ query in the proper way.
The things that are added above are Buttons for Edit, Delete, Update and Cancel which is by default set their enable property to false, this is to prevent users from doing certain actions when the page is loaded in the browser.We just need to create a new object of corresponding database table type, then add it to the Data Context object and then commit the changes. If you want to insert more than one row, then you will have to create a ‘List’ array object containing all the ‘User’ objects and then use ‘Insert All On Submit‘ method, it will work fine.Here is a small block of c# code samples to create new ‘User’ linq to sql class(Representing ‘Users’ Table in Database) and add it to ‘Users Data Context’ class(Represents the database) and commit the changes to original database by ‘Submit Changes'(without this, no changes will be reflected to database): For your information, the above code example is for . If you are using an earlier version, you will have to use ‘Add‘ method instead of ‘Insert On Submit‘ . Deleting data/row from database using linq is as simple as inserting data and this is also sql syntax free operation 🙂 .Aside from that I have also move the form fields inside a Panel control for validation purposes and removed the Read Only attribute for each Text Box.Now the next step if we are going to populate the Drop Down List with the list of customers and populate the form with the customers information based on the customer ID selected from the Drop Down List.
Basically I’m going to show you the basic way on how to edit and delete data from the form and update the database using L2S technology.