C#+winform登陆界面案例

C#+winform登陆界面案例

2018年04月28日 11:27:45 朗文2048 阅读数 6834

 版权声明：本文为博主原创文章，未经博主许可不得转载 https://blog.csdn.net/langwen2048/article/details/80116665

    这俩天做登陆界面设计，也在网上查了一些资料，发现大部分都是针对某个功能介绍，而很少有完整的案列。我呢就结合自己的需求，把有些功能整合在一起了，欢迎大家修改完善。

    SQL数据库设计：

    登陆界面设计：

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.  

12. namespace ZH_controls

13. {

14. public partial class Login : Form

15. {

16. public Login()

17. {

18. InitializeComponent();

19. }

20.  

21. private void Login_Load(object sender, EventArgs e)

22. {

23.  

24. }

25.  

26. private void Login_Button_Click(object sender, EventArgs e) //单击登陆按钮

27. {

28. String username, password;

29. username = UserName.Text;

30. password = Password.Text;

31. String myconn = "Data Source=PC-20180112FRNM;Initial Catalog=属性表;User ID=sa;Password=123;Integrated Security=True";//数据库实例连接字符串

32. SqlConnection sqlConnection = new SqlConnection(myconn);//新建数据库连接实例

33. sqlConnection.Open();//打开数据库连接

34.  

35. password = Adduser.GetMD5(password); //在同一个命名空间（在同一个文件夹中），可以访问Adduser里的GetMD5函数。 因为MD5加密算法不可逆，所以要把输入的密码加密和数据库里密码匹配。这样做以后，除了用户自己谁也不知道密码了。

36. String sql = "select UserName,Password from User_info where UserName='" + username + "'and Password='" + password + "'";//SQL语句实现表数据的读取

37. SqlCommand sqlCommand = new SqlCommand(sql, sqlConnection);

38. SqlDataReader sqlDataReader = sqlCommand.ExecuteReader();

39. if (UserName.Text == "")

40. {

41. MessageBox.Show("请输入用户名", "登陆失败");

42. UserName.Focus();

43. }

44. else if (Password.Text == "")

45. {

46. MessageBox.Show("请输入密码", "登陆失败");

47.  

48. }

49. else

50. {

51. if (sqlDataReader.HasRows)//满足用户名与密码一致，进入下一个界面

52. {

53.                     //实现页面跳转

54. Form1 form3 = new Form1();

55. this.Hide();     //隐藏当前窗体   

56. form3.ShowDialog();

57. Application.ExitThread(); //退出当前窗体，这一步很重要，否则最后可能无法将所有进程关闭。最好是在跳转页面后，将之前的页面退出。

58. }

59. else//如果登录失败，询问是否注册新用户

60. {

61. DialogResult dr = MessageBox.Show("是否注册新用户？", "登录失败", MessageBoxButtons.YesNo, MessageBoxIcon.Question);

62. if (dr == DialogResult.Yes)//打开注册界面

63. {

64.  

65. Adduser form2 = new Adduser();

66. this.Hide();

67. form2.ShowDialog();

68. Application.ExitThread();

69. }

70. else

71. {

72. UserName.Text = "";

73. Password.Text = "";

74. UserName.Focus();

75. this.Show();

76. }

77. }

78. }

79. sqlConnection.Close();

80. }

81.  

82. private void Register_Click(object sender, EventArgs e) //单击注册按钮

83. {

84.  

85. Adduser form2 = new Adduser();

86. this.Hide();

87. form2.ShowDialog();

88. Application.ExitThread();

89. }

90.  

91. private void Quit_Click(object sender, EventArgs e) //单击退出按钮

92. {

93. Application.Exit();

94. }

95.  
96.  

97. private void UserName_KeyPress(object sender, KeyPressEventArgs e) //功能：输入用户名后，按 Enter键，光标到输入密码的TextBox中

98. {

99. if (e.KeyChar == (char)Keys.Enter)

100. {

101. Password.Focus(); //控制光标指向哪的

102. }

103. }

104.  

105. private void Password_KeyPress(object sender, KeyPressEventArgs e) //KeyPress事件，在控件具有焦点并且用户按下并释放某个键后发生

106. {

107. if (e.KeyChar == (char)Keys.Enter)

108. {

109. // Login_Button.Focus();

110. Login_Button_Click(sender ,e);

111. }

112. }

113.  

114. }

115. }

注册页面设计：

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. using System.Security.Cryptography; //MD5密码加密

11.  

12. namespace ZH_controls

13. {

14. public partial class Adduser : Form

15. {

16. public Adduser()

17. {

18. InitializeComponent();

19. }

20.  

21. private void button1_Click(object sender, EventArgs e) //单击确定按钮

22. {

23. String username, password, repassword;

24. username = textBox1.Text;

25. password = textBox2.Text;

26. repassword = textBox3.Text;

27. if (textBox1.Text == "")

28. {

29. MessageBox.Show("请输入用户名", "注册失败");

30. textBox1.Focus();

31. }

32. else if (textBox2.Text == "")

33. {

34. MessageBox.Show("请输入密码", "注册失败");

35. textBox2.Focus();

36. }

37. else if (textBox3.Text == "")

38. MessageBox.Show("请确认密码", "注册失败");

39. else

40. {

41. string myConn = "Data Source=PC-20180112FRNM;Initial Catalog=属性表;User ID=sa;Password=123;Integrated Security=True";

42. SqlConnection sqlConnection = new SqlConnection(myConn); //实例化连接对象

43. sqlConnection.Open();

44. String sql = "select UserName from User_info where UserName='" + username + "'";//SQL语句实现表数据的读取

45. SqlCommand sqlCommand = new SqlCommand(sql, sqlConnection);

46. SqlDataReader sqlDataReader = sqlCommand.ExecuteReader();

47.  

48. if (sqlDataReader.HasRows)

49. {

50. sqlConnection.Close();

51. MessageBox.Show("该用户名已存在，请重新注册", "注册失败");

52. textBox1.Text = "";

53. textBox2.Text = "";

54. textBox3.Text = "";

55. textBox1.Focus(); //指定光标在哪个textBox处闪烁

56. }

57. else

58. {

59. if (password == repassword)//两次输入的密码一致

60. {

61. sqlConnection.Close();

62. string myConn2 = "Data Source=PC-20180112FRNM;Initial Catalog=属性表;User ID=sa;Password=123;Integrated Security=True";

63. SqlConnection sqlConnection2 = new SqlConnection(myConn2); //实例化连接对象

64. sqlConnection.Open();

65.  

66. password = GetMD5(password);

67. String sql2 = "INSERT INTO User_info(UserName,Password) VALUES('" + username + "','" + password + "')";//SQL语句向表中写入数据

68. SqlCommand sqlCommand2 = new SqlCommand(sql2, sqlConnection);

69. sqlCommand2.ExecuteNonQuery();

70. sqlConnection2.Close();

71. DialogResult dr = MessageBox.Show("是否返回主界面", "注册成功", MessageBoxButtons.YesNo, MessageBoxIcon.Question);

72. if (dr == DialogResult.Yes)//打开注册界面

73. {

74.  

75. Login form2 = new Login();

76. this.Hide();

77. form2.ShowDialog();

78. Application.ExitThread();

79. }

80. else

81. {

82. textBox1.Text = "";

83. textBox2.Text = "";

84. textBox3.Text = "";

85. this.Show();

86. }

87.  

88. }

89. else

90. {

91. MessageBox.Show("两次输入密码不一致", "错误信息");

92. textBox1.Text = "";

93. textBox2.Text = "";

94. textBox3.Text = "";

95. }

96. }

97. }

98. }

99.  

100. private void button2_Click(object sender, EventArgs e) //返回登陆按钮

101. {

102. Login form3 = new Login();

103. this.Hide();

104. form3.ShowDialog();

105. Application.ExitThread();

106.  

107. }

108.  

109. public static string GetMD5(String input) //MD5算法，输入一段字符串，输出一段字符串

110. {

111. string cl = input;

112. string pwd = "";

113. MD5 md5 = MD5.Create();//实例化一个md5对像

114. // 加密后是一个字节类型的数组，这里要注意编码UTF8/Unicode等的选择　

115. byte[] s = md5.ComputeHash(Encoding.UTF8.GetBytes(cl));

116. // 通过使用循环，将字节类型的数组转换为字符串，此字符串是常规字符格式化所得

117. for (int i = 0; i < s.Length; i++)

118. {

119. // 将得到的字符串使用十六进制类型格式。格式后的字符是小写的字母，如果使用大写（X）则格式后的字符是大写字符

120.  

121. pwd = pwd + s[i].ToString("X");

122.  

123. }

124. return pwd;

125. }

126.  

127. private void textBox1_KeyPress(object sender, KeyPressEventArgs e)

128. {

129. if (e.KeyChar == (char)Keys.Enter)

130. {

131. textBox2.Focus();

132. }

133. }

134.  

135. private void textBox2_KeyPress(object sender, KeyPressEventArgs e)

136. {

137. if (e.KeyChar == (char)Keys.Enter)

138. {

139. textBox3.Focus();

140. }

141. }

142.  

143. private void textBox3_KeyPress(object sender, KeyPressEventArgs e)

144. {

145. if (e.KeyChar == (char)Keys.Enter)

146. {

147. button1_Click(null, null);

148. }

149. }

150.  
151.  
152.  

153. }

154. }