ADO.NET之5-使用Command对象删除记录---ShinePans
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2022-05-18 19:59:04
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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