源代码: 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) { //连
源代码:
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)
 {
 //连接数据库
 string connection =
 "server=潘尚\\SQLEXPRESS;database=db_test;Trusted_Connection=true";
 SqlConnection sc = new SqlConnection(connection);
 sc.ConnectionString = connection;
 try
 {
 sc.Open(); //打开数据库连接
 Console.WriteLine("已经打开数据库连接!");
 string cmdtext = "DELETE FROM db_student WHERE student_name=@name";
 SqlCommand cmd = new SqlCommand(cmdtext, sc);
 cmd.Parameters.Add("@name", SqlDbType.VarChar).Value = "潘";
 int i = cmd.ExecuteNonQuery();
 if (i > 0) Console.WriteLine("删除记录成功!");
 //////添加记录的代码//////
 /* SqlCommand cmd = new SqlCommand();//创建SqlCommand对象
 cmd.CommandType = CommandType.Text; //设置执行文本命令
 cmd.Connection = sc; //设置对象属性
 cmd.CommandText = 
 "INSERT INTO db_student(student_name,student_age,student_address,student_grade)VALUES(@name,@age,@address,@grade)";
 //添加参数并为参数赋值
 cmd.Parameters.Add("@name", SqlDbType.VarChar, 10).Value = "潘";
 cmd.Parameters.Add("@age", SqlDbType.Int).Value = 19;
 cmd.Parameters.Add("@address", SqlDbType.VarChar).Value = "武汉";
 cmd.Parameters.Add("@grade", SqlDbType.Int).Value = 100;
 int i = cmd.ExecuteNonQuery(); //执行数据库添加记录命令
 if (i > 0) Console.WriteLine("添加记录成功"); //控制台输出添加记录
 * ////添加记录的代码///////*/
 }
 catch (Exception ex)
 {
 Console.WriteLine("打开数据库错误:{0}", ex.Message);
 }
 finally
 {
 sc.Close();
 Console.WriteLine("数据库连接已关闭!");
 }
 System.Console.ReadLine();
 }
 }
}
删除执行: 
删除后的状态:
总结:注意cmdtext的正确性
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