做课程设计的时候遇到了麻烦,希望各位老师给指点指点!
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Data.SqlClient;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
namespace 成绩管理
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
private void Form1_Load(object sender, EventArgs e)
{
comboBox1.Items.Add("学生登录");
comboBox1.Items.Add("教师登录");
comboBox1.SelectedIndex = 0;
comboBox1.DropDownStyle = ComboBoxStyle.DropDownList;
}
private void button1_Click(object sender, EventArgs e)
{
string cstr = @"Data Source=.;Initial Catalog=login;Integrated Security=True";
string sql = string.Format("select count(*) from login where Name='{0}'and Pwd='{1}'", textBox1.Text.Trim(), textBox2.Text.Trim());
using (SqlConnection conn = new SqlConnection(cstr))
{
using (SqlCommand cmd = new SqlCommand(sql, conn))
{
conn.Open();
MessageBox.Show("连接成功!");
int n = Convert.ToInt32(cmd.ExecuteScalar());
if (n >= 1)
{
if (comboBox1.SelectedText.Equals("学生登录"))
{
&nbs