Ado. NET 5-delete records using Command object---Shinepans

Source:

Using system;using system.collections.generic;using system.data;using system.data.sqlclient;using System.Linq;using        System.text;using System.threading.tasks;namespace sqltest{class Program {static void Main (string[] args) {//Connection database String connection = "server= Pinchamp \\sqlexpress;database=db_test;            Trusted_connection=true ";            SqlConnection sc = new SqlConnection (connection); Sc.            ConnectionString = connection; try {sc.  Open ();                Open the Database connection Console.WriteLine ("Already Open database connection!");                String cmdtext = "DELETE from db_student WHERE [email protected]";                SqlCommand cmd = new SqlCommand (Cmdtext, SC); Cmd. Parameters.Add ("@name", SqlDbType.VarChar).                Value = "Pan"; int i = cmd.                ExecuteNonQuery ();                if (i > 0) Console.WriteLine ("Delete record successfully!"); Add a record code///////* SqlCommand cmd = new SQLCommand ();//Create SqlCommand object cmd. CommandType = CommandType.Text; Sets the Execute text command cmd. Connection = SC; Sets the object property of CMD. CommandText = "INSERT into Db_student (student_name,student_age,student_address,student_grade) VALUES (@n                Ame, @age, @address, @grade) "; Add a parameter and assign a value cmd to the parameter. Parameters.Add ("@name", SqlDbType.VarChar, 10).                Value = "Pan"; Cmd. Parameters.Add ("@age", SqlDbType.Int).                Value = 19; Cmd. Parameters.Add ("@address", SqlDbType.VarChar).                Value = "Wuhan"; Cmd. Parameters.Add ("@grade", SqlDbType.Int).                Value = 100; int i = cmd. ExecuteNonQuery (); Execute database Add record command if (i > 0) Console.WriteLine ("Add record Success"); Console output Add record *////add record code///////*/} catch (Exception ex) {Co Nsole. WriteLine ("Open database error: {0}", ex.)            Message); } finally {SC.               Close (); Console.WriteLine ("Database connection closed!");        } System.Console.ReadLine (); }    }}

Delete execution:

The state after deletion:

Summary: Pay attention to the correctness of Cmdtext