C#_会员管理系统：开发五（用户注册）

创建一个新的用户注册窗体(VIPRegistration.cs):

用户注册窗体(VIPRegistration.cs)详细代码如下：

 using System;
 using System.Collections.Generic;
 using System.ComponentModel;
 using System.Data;
 using System.Drawing;
 using System.Linq;
 using System.Text;
 using System.Threading.Tasks;
 using System.Windows.Forms;
 using System.Data.SqlClient;
 using System.Configuration;

 namespace 会员管理系统
 {
     public partial class VIPRegistration : Form
     {
         public VIPRegistration()
         {
             InitializeComponent();
         }

         //提交按钮
         private void btnOK_Click(object sender, EventArgs e)
         {

             string connstr = ConfigurationManager.ConnectionStrings["str"].ConnectionString;
             SqlConnection conn = new SqlConnection(connstr);
             string sql = string.Format("select vusername from VipAccount where vUserName='{0}' ",txtName.Text);
             SqlCommand cmd = new SqlCommand(sql, conn);
             conn.Open();
             SqlDataReader sda=cmd.ExecuteReader();

             if (txtName.Text.Trim() == "")
             {
                 lblName.Text="用户名不能为空";
                 return;
             }
             else if (txtPwd.Text.Trim() == ""|| txtPwdConfirm.Text.Trim()=="")
             {
                 lblPwd.Text = "密码不能为空";
                 return;
             }
             else if (txtPwdConfirm.Text.Trim()!= txtPwd.Text.Trim())
             {
                 lblPwdConfirm.Text = "两次密码输入不同，请确认后再输";
                 return;
             }
             else if (sda.Read())
             {
                 lblName.Text = "用户名已存在，请重新输入";
                 return;
             }
             else
             {
                 conn.Close();
                 SqlConnection conninsert = new SqlConnection(connstr);
                 string insertsql = string.Format("insert into VipAccount(vUserName,vUserPwd) values('{0}','{1}')",txtName.Text,txtPwd.Text);
                 SqlCommand cmdinsert = new SqlCommand(insertsql, conninsert);
                 conninsert.Open();
                 int n = cmdinsert.ExecuteNonQuery();
                 if (n == )
                 {
                     MessageBox.Show("注册失败，请重新输入");
                 }
                 else
                 {
                     MessageBox.Show("注册成功");
                 }
                 conninsert.Close();

             }
             //conn.Close();
         }

         //返回主菜单
         private void btnBack_Click(object sender, EventArgs e)
         {
             VIPMain vm = new VIPMain();
             vm.Show();
             this.Hide();
         }

         private void VIPRegistration_Load(object sender, EventArgs e)
         {
             lblName.Text = "";
             lblPwd.Text = "";
             lblPwdConfirm.Text = "";
         }

     }
 }

主界面窗体(VIPMain.cs)添加一个新的按钮：

用户注册按钮代码：

         private void btnRegistration_Click(object sender, EventArgs e)
         {
             VIPRegistration vrn = new VIPRegistration();
             vrn.Show();
             this.Hide();
         }