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Question

我数据库中有一表，我输入两个值和表中第二列第三列的值比较，实现简单的密码验证，可每次都显示“用户名或密码错误”
代码如下，该怎么解决？
 SqlConnection con = new SqlConnection("server=.;database=superet;Trusted_Connection=True");          
                SqlCommand cmd = new SqlCommand();
                con.Open();
                cmd.Connection = con;
                string str = "select * from ad;";
                SqlDataAdapter ada = new SqlDataAdapter(str, con);
                DataTable dt = new DataTable();               
                dt=new DataTable();
                ada.Fill(dt);
                int i,j=0;
                for (i = 0; i < dt.Rows.Count; i++)
                {                    
                    if ((textBox1.Text.ToString() == (dt.Rows[i][1].ToString())) && (textBox2.Text.ToString() == (dt.Rows[i][2].ToString())))               
                    {
                        MessageBox.Show("成功");
                        j = 1;
                    }                                 
                }
                if(j==0)
                {
                    MessageBox.Show("用户名或密码错误");
                }

Answer 1

断点调试看一上值呀...........