Here I will explain how to delete selected data from a database, before this I explain how to update or edit data.

Step 1: Registration form with delete button

delete button

Drag and drop a button from the toolbox and provide it the name Delete.

Step 2: The following is the code:
code

Double-click on the Delete button and write the following code.
  1. private void Delete_txt_Click(object sender, EventArgs e)
  2. {
  3. if (!(id_txt.Text == string.Empty))
  4. {
  5. string str = "server = MUNESH\\SQL2008R2;Database=datastore;UID=sa;Password=reladmin@123;";
  6. SqlConnection con = new SqlConnection(str);
  7. string query = "Delete from data1 where ID= '" + this.id_txt.Text + "'";
  8. SqlCommand cmd = new SqlCommand(query, con);
  9. SqlDataReader myreader;
  10. try
  11. {
  12. con.Open();
  13. myreader = cmd.ExecuteReader();
  14. MessageBox.Show("successfully data Deleted","user information");
  15. while (myreader.Read())
  16. {
  17. }
  18. con.Close();
  19. }
  20. catch (Exception ec)
  21. {
  22. MessageBox.Show(ec.Message);
  23. }
  24. }
  25. else
  26. {
  27. MessageBox.Show("enter ID which you want to delete","User information");
  28. }
  29. }

Step 3: Output

Run your project and enter an ID and click on the delete button.

Output
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