private void denglubutton_Click(object sender, EventArgs e) { //MessageBox.Show(Convert.ToString(yonghuming_textbox.Text == null)); string source = "server=(local) \\SQLEXPRESS;database=users;integrated security=SSPI"; SqlConnection con = new SqlConnection(source); con.Open();//打开数据库 if (con.State == ConnectionState.Open) { MessageBox.Show("数据库连接成功!"); } string select = "select * from yonghu"; SqlDataAdapter sda = new SqlDataAdapter(select, con); DataSet ds = new DataSet(); sda.Fill(ds, "yonghu"); int flag = 0;//设置一个标记,判断用户是否登录成功 foreach (DataRow x in ds.Tables["yonghu"].Rows) { if (yonghuming_textbox.Text == x["id"].ToString().Trim() && yonghumina_textbox.Text == x["mima"].ToString().Trim()) { yonghuid = yonghuming_textbox.Text; yonghumima = yonghumina_textbox.Text; yonghuname = x["name"].ToString().Trim(); flag = 1; //MessageBox.Show(x["name"].ToString()); //如果yonghu数据库中的name不为空,则进入用户界面 if (x["name"].ToString().Trim() != String.Empty)//此处用String.Empty而不用null是因为数据库中为赋值的行为“”而不是null { //if() yuhujiemian f3 = new yuhujiemian(); f3.ShowDialog(); } //否则进入绑定界面 else { yonghubangding yhbd = new yonghubangding(); yhbd.ShowDialog(); } } } if (flag == 0)//如果没有登录成功,则显示 { MessageBox.Show("用户名或密码错误!", "提示", MessageBoxButtons.OK, MessageBoxIcon.Warning); } }
private void button1_Click(object sender, EventArgs e) { string select = "select cname from customers"; con = new SqlConnection(source); con.Open(); if (con.State == ConnectionState.Open) { MessageBox.Show("数据库连接成功!"); } sda = new SqlDataAdapter(select, con); sda.Fill(ds, "name"); //MessageBox.Show("lalala!"); int flag = 0;//判断customers中是否有输入的姓名 foreach (DataRow x in ds.Tables["name"].Rows) { if (textBox1.Text == x["cname"].ToString().Trim()) { flag = 1;//有的话赋值为1 MessageBox.Show("有这个姓名!"); con2 = new SqlConnection(source2); string select2 = "select * from yonghu"; sda = new SqlDataAdapter(select2, con2); sda.Fill(ds2, "yonghu"); foreach (DataRow y in ds2.Tables["yonghu"].Rows) { if (y["id"].ToString().Trim() == yonghuyanzhengjiemian.yonghuid) { y["name"] = textBox1.Text; SqlCommandBuilder scb = new SqlCommandBuilder(sda); sda.Update(ds2, "yonghu"); yonghuyanzhengjiemian.yonghuname = textBox1.Name.Trim();//保存用户名字,方便以后的查询用户个人信息等操作 MessageBox.Show("会员绑定成功!"); //yonghuyanzhengjiemian.yonghuname= yuhujiemian yh = new yuhujiemian(); yh.ShowDialog(); } } } } if (flag == 0) { MessageBox.Show("你还不是会员!请联系管理员"); } }