C#简单的登陆界面！

柔情只为你懂 2022-06-01 00:50 170阅读 0赞

using System;
    using System.Collections.Generic;
    using System.ComponentModel;
    using System.Data;
    using System.Drawing;
    using System.Linq;
    using System.Text;
    using System.Windows.Forms;
    using System.Data.OleDb;
    namespace WindowsFormsApplication58
    {
        public partial class Form1 : Form
        {
            public Form1()
            {
                InitializeComponent();
            }
            int limit=0;//记录下用户的权限，以此来区别什么用户能打开什么菜单
            private void button1_Click(object sender, EventArgs e)
            {
                //检索数据库里是否有该数据
                string str = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=db1.mdb;";
                OleDbConnection mycon=new OleDbConnection(str);
                string sql="select * from 权限 where 账号= '"+ textBox1.Text +"' " + "and 密码= '"+ textBox2.Text+"' ";
                OleDbCommand mycom = new OleDbCommand(sql, mycon);
                mycon.Open();
                OleDbDataReader reader = mycom.ExecuteReader();
                if (reader.Read())
                {
                    limit = Convert.ToInt32( textBox1.Text);
                    switch(limit)
                    {
                        case 1:
                            menu1.Enabled = true;break;
                        case 2:
                            menu2.Enabled = true;break;
                        case 3:
                            menu3.Enabled = true;break;
                        default:
                            MessageBox.Show("您没有使用本软件的权限！", "警告");break;
    
                    }
    
                    
                    MessageBox.Show("登陆成功", "消息");
                }
                else
                {
                    MessageBox.Show("登陆失败，请确保账号和密码无误", "消息");
                }
                    
            }
    
            private void Form1_Load(object sender, EventArgs e)
            {
                menu1.Enabled = false;
                menu2.Enabled = false;
                menu3.Enabled = false;
            }
    
           
        }
    }

前提是要建立好密码账号的数据库。

效果图如下：

![1345885774_1593.jpg][]

[1345885774_1593.jpg]: https://img-my.csdn.net/uploads/201208/25/1345885774_1593.jpg