Help Please RSS

• • Reply
  Donald416

  Member

  18 Points

  98 Posts

  Help Please

  Mar 28, 2019 03:18 AM|Donald416|LINK

  I am trying to set a command that will do the following things at the click of a button:

  The first is to check an already existed e-mail in the database, and then if the e-mail is not in the database, it should go ahead and save the new e-mail, else it should state that the “e-mail entered already exists”.

  In that same class, there should be a command to reject empty textboxes.

  I will be glad if I get answers to this problem I am having in my project work.

  Thank you.

  My Aspx.cs code:

  using System;
  using System.Collections.Generic;
  using System.Linq;
  using System.Web;
  using System.Data;
  using System.Web.UI;
  using System.Web.UI.WebControls;
  using System.Web.UI.WebControls.WebParts;
  using System.Web.UI.HtmlControls;
  using System.Data.SqlClient;
  
  public partial class Login : System.Web.UI.Page
  {
      SqlConnection con = new SqlConnection("Data Source=(LocalDB)\\MSSQLLocalDB;AttachDbFilename=|DataDirectory|\\Dataregister.mdf;Integrated Security=True");
      protected void Page_Load(object sender, EventArgs e)
      {
  
      }
  
      protected void Button2_Click(object sender, EventArgs e)
      {
          SqlCommand cmd = new SqlCommand();
          con.Open();
          cmd.CommandText = "Select * from [Table] where mail=@email";
          cmd.Parameters.AddWithValue("@email", emtxt.Text);
          cmd.Connection = con;
          SqlDataReader dr = cmd.ExecuteReader();
          if (dr.HasRows)
          {
              Label9.Visible = true;
              Label9.Text = "e-mail alreay exists";
              Label9.ForeColor = System.Drawing.Color.Red;
          }
      
         else if (emtxt.Text != "" & signutxt.Text != "" & passtxt.Text != "")
          {
              string ins = "insert into [Table](mail, user_name, pass) values('" + emtxt.Text + "','" + signutxt.Text + "','" + passtxt.Text + "')";
              {
                  SqlCommand com = new SqlCommand(ins, con);
                  con.Open();
                  com.ExecuteNonQuery();
                  info.Text = "Sign Up Successful";
                  info.ForeColor = System.Drawing.Color.Green;
                  emtxt.Text = "";
                  signutxt.Text = "";
                  passtxt.Text = "";
                  // Response.Redirect("Register.aspx");
              }
              con.Close();
  
          }
          else
          {
              info.ForeColor = System.Drawing.Color.Red;
              info.Text = "*All Fields Are Required*";
              emtxt.Text = "";
              signutxt.Text = "";
              passtxt.Text = "";
          }
      }
  

• • Reply
  Ackerly Xu

  Contributor

  3480 Points

  1300 Posts

  Re: Help Please

  Mar 28, 2019 07:24 AM|Ackerly Xu|LINK

  Hi Donald416,

  From your code , I think it has meet your require , if the email has existed, don't insert and show error message , if any of mail, user_name, pass is empty ,don't insert and show error message.

  What's your problem?

  If you want to simplify your code , you could try the code below.

  if (emtxt.Text != "" & signutxt.Text != "" & passtxt.Text != "")
          {using (SqlConnection con = new SqlConnection(constr))
                  {
                      using (SqlCommand com = new SqlCommand("if not exists ( select count(*) from [table] where mail=@mail ) begin insert into [Table](mail, user_name, pass) values(@newmail, @username,@pass) end", con))
                      {
                       // add your parameters
                             con.Open();
                         com.ExecuteNonQuery();
                     //  you could know whether  the record is inserted through the returned value of com.ExecuteNonQuery
                      // if is -1, no record is inserted
                      }
                  }
             }

  Best regards,

  Ackerly Xu       

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