C#用户登录验证问题

Question

SqlConnection LoginConnection = new SqlConnection(@"Data source = (local);Initial Catalog = booksalesystem;Integrated Security = True;Connect Timeout = 30");
            SqlDataAdapter LoginAdapter = new SqlDataAdapter("SELECT AdministratorAccount, AdministratorPassword FROM Administrator WHERE AdministratorAccount = AccountBox.Text", LoginConnection);
            DataTable LoginDataTable =new DataTable();
            LoginAdapter.Fill(LoginDataTable);
            if (LoginDataTable.Rows.Count > 0)
            {
                if ((string)LoginDataTable.Rows[0][1] == PasswordBox.Text)
                {
                    AdministratorForm LoginAdForm = new AdministratorForm();
                    this.Close();
                    LoginAdForm.Show();   
                }
                else
                {
                    MessageBox.Show("密码输入错误！", "圣灵图书销售");
                    return;
                }
            }
            else
            {
                MessageBox.Show("账号输入错误！", "圣灵图书销售");
                return;
            }
        }
为什么说  无法绑定由多个部分组成的标识符 "AccountBox.Text"

Answer 1

AdministratorAccount = " + AccountBox.Text.ToString() + ", 

Answer 2

如果是字符型的话 AdministratorAccount = "'" + AccountBox.Text.ToString() + "'"