C# login window and validation (+SQL)

Team members and division of labor

Team: There are six members in Team Blue

Last four digits: Contribution Score:

Zhang Yu (Team leader) 1152 1+1.7=2.7 points

1+1=2 points

1+1=2 points

Li Jincheng 1040 1+0.3=1.3 points

Zhang Yumian 1153 1 points

Kanghe 11691 minutes

1. Determine the team member performance evaluation method –> individual performance in the team

2. Zhang Yu and Hou Heqi are responsible for demand analysis and design ideas

3. Kang He and Zhang Yumian are responsible for interface design and documentation

4. Specific coding (programming) Each team member should take responsibility for what they think they can accomplish

5. Ding Zhili and Li Jincheng are responsible for testing and debugging

Objective: To promote the learning of all team members in order to successfully complete team tasks.

A Whether to arrive on time for each collection

B Whether it can promote team unity.

C is able to complete coding tasks in team work on time

D Whether can submit daily work log on time

To meet the above requirements, everyone will be scored according to their contribution to the team. Any behavior that is not conducive to team unity and project progress will be deducted corresponding points.

User requirements:

You can log in by entering your username and password! And at the time of login, if the user name does not exist, or the password is wrong, at this time to give a hint!

Specific design ideas:

Step 1: Create a database! After all, you can’t log in without a user, right? Create a new database named REPAIR in VS Server Explorer, add a table named user_info, and insert two test records! Step 2: create a new form, place three Lable, two text boxes, two buttons, give each control a good Name to remember, the interface layout! Create a DBConn class and wrap the connection string in dbconn.cs. Step 4: Look at the code ↓↓↓

Code implementation:

DBConn.cs

1 using System; 2 using System.Collections.Generic; 3 using System.Linq; 4 using System.Text; 5 using System.Data.SqlClient; 6 using System.Data; 6 8 Namespace sixth 9 {10 class DBConn 11 {12 public static string connStr = "Data Source=.; Initial Catalog=repair; Integrated Security=True; Pooling=False"; 14 public static SqlConnection conn = new SqlConnection(connStr); 16 15}}Copy the code

FormLogin.cs

1 using System; 2 using System.Collections.Generic; 3 using System.ComponentModel; 4 using System.Data; 5 using System.Drawing; 6 using System.Linq; 7 using System.Text; 8 using System.Windows.Forms; 9 using System.Data.SqlClient; 10 11 namespace sixth 12 { 13 public partial class FormLogin : Form 14 { 15 public FormLogin() 16 { 17 InitializeComponent(); 18 } 19 20 private void btnLogin_Click(object sender, EventArgs e) 21 {22 try 23 {24 if (txtusn.text.trim () == "") 25 {26 labmessage.text =" " ; 27 txtUsn.Focus(); // get focus 28 return; 29} 30 else if (txtpwd.text.trim () == "") 31 {32 labmessage.text =" " ; 33 txtPwd.Focus(); 34 return; 35} 36 37 // The teacher said: the following method will be through the text box input SQL statement to malicious damage to the database is possible, so use the form of parameters to get the value of the text box! 38 //string sqlStr = "select userName,passWord from user_info where userName='" + txtUsn.Text.Trim() + "'"; 39 40 string sqlStr = "select userName,passWord from user_info where userName=@userName"; 41 DataSet ds = new DataSet(); 42 DBConn.conn.ConnectionString = DBConn.connStr; 43 DBConn.conn.Open(); 44 SqlCommand cmd = new SqlCommand(sqlStr, DBConn.conn); 45 cmd.Parameters.Add(new SqlParameter("@userName", SqlDbType.VarChar, 50)); 46 cmd.Parameters[" @username "].Value = txtusn.text; SqlDataReader SDR = cmd.executereader (); SqlDataReader SDR = cmd.executereader (); 48 if (! Sdr.read ()) 49 {50 labmessage.text = "userName does not exist! Please re-enter "; 51 txtUsn.Text = ""; // Empty the textbox 52 txtpwd. Text = ""; 53 txtUsn.Focus(); 59} 55 else if (SDR ["passWord"].toString ().trim () == txtpwd.text.Trim()) 56 {57 labmessage.text = "Congratuations.log" ; 58} 59 else 60 {61 labmessage. Text = "Password error! Please re-enter!" ; 62 txtPwd.Text = ""; 63 txtPwd.Focus(); 64} 65} 66 catch (Exception ex) 67 {68 labmessage. Text = "error:" + ex. 69 txtUsn.Text = ""; 70 txtPwd.Text = ""; 71 txtUsn.Focus(); 72 } 73 finally 74 { 75 DBConn.conn.Close(); // The most important thing is to close the database! 76 } 77 } 78 79 private void btnCancel_Click(object sender, EventArgs e) 80 { 81 Application.Exit(); // Exit 82} 83} 84}Copy the code

Testing:

1. Database, forms and test data



2. Login is successful



3. The user name does not exist. In fact, when the user name does not exist, the text field is left blank

Easy to show



4. The password is incorrect, and the password text box is empty

PSP Time analysis:

Team programming summary:

A team, to do a good job in a project, to have a very comprehensive consideration and analysis. Perhaps one person could not fully consider the whole project, so **Team Leader first organized a meeting to collect everyone’s opinions. In fact, this time, everyone is very active cooperation, individual comrades due to various reasons, everyone can understand. But we always follow a principle, work more, get more! In fact, this is just a start, but we still have to follow the process to complete the task, to do a perfect start, then the follow-up work can come. 支那

******** personal summary of team programming: Hou Heqi: This assignment is relatively easy, of course, compared to our team leader. He deserves a lot of credit for driving us to the finish line. Although the task is simple, but the captain is still divided into several small tasks to complete given to us, the homework useful knowledge to the database, database is the most weak, I have to pick up the previous knowledge, when I face the library is really hurry-scurry panic in a big mess, after all is hang up database last term, but it was no use, the key moment still have to rely on the captain, At this time, the captain came forward to make up the database connection knowledge, and finally completed it. In fact, Windows application is very good, I like the form square. In fact, how to say, code this thing with me, I am not so like, freshman HTML is purely boring to learn to play, there is a little like in it, in sophomore, in fact, or blame yourself, quite many will not. Zhang Yu is really moving to lead us to study, I think he should be the most likely to take this road, I hope he can succeed. \

** D Volunteer: **

After the last team work, we are full of confidence for this assignment. Although the homework this time is not very much, but we still according to the requirements, reasonable division of labor, each member of their own work to do very well. This project is just the beginning, but it is an important step, the login interface. After the last project, the members of the team are more comfortable this time. Everyone completes their work conscientiously. Through the team mode again and again, we know more about ourselves. Every cooperation is a growth, no matter how difficult the assignment is, we will try our best. After each cooperation, we have encountered a lot of difficulties, database is the course of last semester, in the process of cooperation, we are helping each other, sometimes there will be complaints, sometimes there will be complaints, but with our mutual help, we have overcome these problems. Every difficulty is a test on the way of growth, after a test, we will grow up again and again. I believe that after each teamwork, we will learn more and strive to overcome our shortcomings and increase our abilities. In the future, we will learn more and increase our ability step by step.