利用MD5加密数据库中的密码

1    ```
2@ Import Namespace="System.Text" 

1    ```
2@ Import Namespace="System.Data.SqlClient" 

 1<script language="VB" runat="server">
 2        Sub CreateAccount(sender as Object, e as EventArgs)
 3          '1. 创建连接
 4          Const strConnString as String 
 5          strConnString= "Data Source=.;Initial Catalog=test;User Id=sa;Password=;"
 6          Dim objConn as New SqlConnection(strConnString)
 7          
 8          '2. 创建Command对象
 9          Dim strSQL as String = _
10              "INSERT INTO UserAccount(Username,Password) " & _
11              "VALUES(@Username, @Password)"
12          Dim objCmd as New SqlCommand(strSQL, objConn)
13          
14          '3. 创建参数
15          Dim paramUsername as SqlParameter
16          paramUsername = New SqlParameter("@Username", SqlDbType.VarChar, 25)
17          paramUsername.Value = txtUsername.Text
18          objCmd.Parameters.Add(paramUsername)
19          
20      
21          '加密密码字段
22    
23           **Dim md5Hasher as New MD5CryptoServiceProvider()
24        
25          Dim hashedBytes as Byte()   
26          Dim encoder as New UTF8Encoding()
27    
28          hashedBytes = md5Hasher.ComputeHash(encoder.GetBytes(txtPwd.Text))      
29    
30          Dim paramPwd as SqlParameter
31          paramPwd = New SqlParameter("@Password", SqlDbType.Binary, 16)
32          paramPwd.Value = hashedBytes
33          objCmd.Parameters.Add(paramPwd)**
34          
35          
36          '插入数据库
37          objConn.Open()
38          objCmd.ExecuteNonQuery()
39          objConn.Close()
40          
41          _'Redirect 其它页面_
42        End Sub
43    </script>

1<form runat="server">
2<h1>创建帐号：</h1>
3      用户名: <asp:textbox id="txtUsername" runat="server"></asp:textbox>
4      
5
6      密码: <asp:textbox id="txtPwd" runat="server" textmode="Password"></asp:textbox>
7<p><asp:button onclick="CreateAccount" runat="server" text="创建用户"></asp:button></p>
8</form>

1    ```
2@ Import Namespace="System.Text" 

1    ```
2@ Import Namespace="System.Data.SqlClient" 

 1<script language="VB" runat="server">
 2        Sub Login(sender as Object, e as EventArgs)
 3          '1. 创建连接
 4          Const strConnString as String 
 5          strConnString= "Data Source=.;Initial Catalog=test;User Id=sa;Password=;"
 6          Dim objConn as New SqlConnection(strConnString)
 7          
 8          '2. 创建Command对象
 9          Dim strSQL as String = "SELECT COUNT(*) FROM UserAccount " & _
10                            "WHERE Username=@Username AND Password=@Password"
11          Dim objCmd as New SqlCommand(strSQL, objConn)
12          
13          '3. 创建参数
14          Dim paramUsername as SqlParameter
15          paramUsername = New SqlParameter("@Username", SqlDbType.VarChar, 25)
16          paramUsername.Value = txtUsername.Text
17          objCmd.Parameters.Add(paramUsername)
18          
19      
20          '加密密码
21          Dim md5Hasher as New MD5CryptoServiceProvider()
22        
23          Dim hashedDataBytes as Byte()   
24          Dim encoder as New UTF8Encoding()
25    
26          hashedDataBytes = md5Hasher.ComputeHash(encoder.GetBytes(txtPwd.Text))      
27    
28          Dim paramPwd as SqlParameter
29          paramPwd = New SqlParameter("@Password", SqlDbType.Binary, 16)
30          paramPwd.Value = hashedDataBytes
31          objCmd.Parameters.Add(paramPwd)
32          
33          
34          '执行查询
35          objConn.Open()
36          Dim iResults as Integer = objCmd.ExecuteScalar()
37          objConn.Close()
38          
39          If iResults = 1 then
40            '合法
41          Else
42            '不合法
43          End If
44        End Sub
45    </script>

1<form runat="server">
2<h1>登录：</h1>
3      用户名:<asp:textbox id="txtUsername" runat="server"></asp:textbox>
4 
5      密  码:<asp:textbox id="txtPwd" runat="server" textmode="Password"></asp:textbox>
6<p><asp:button onclick="Login" runat="server" text="登录"></asp:button>
7</p></form>

1    ```
2@ Import Namespace="System.Text" 

 1<script language="VB" runat="server">
 2      Sub DisplayEncryptedText(sender as Object, e as EventArgs)
 3        If Page.IsValid then
 4          Dim md5Hasher as New MD5CryptoServiceProvider()
 5        
 6          Dim hashedDataBytes as Byte()   
 7          Dim encoder as New UTF8Encoding()
 8    
 9          hashedDataBytes = md5Hasher.ComputeHash(encoder.GetBytes(txtPassword.Text))    
10        
11          ltlResults.Text = "<b>Encrypted Results</b><br /> The results are encrypted into " & _
12                  "an array of 16 bytes.  These 16 bytes contain the values:<p><ul>"
13        
14          Dim b as Byte
15          For Each b in hashedDataBytes
16    	    ltlResults.Text &= "<li>" & b & "</li>"
17          Next b
18          
19          ltlResults.Text &= "</ul>"    
20        End If
21      End Sub  
22    </script>

 1<form runat="server">
 2      Enter a string:
 3      <asp:textbox id="txtPassword" runat="server"></asp:textbox>
 4<asp:requiredfieldvalidator controltovalidate="txtPassword" display="Dynamic" errormessage="&lt;i&gt;You must provide a value here...&lt;/i&gt;" runat="server"></asp:requiredfieldvalidator>
 5<asp:regularexpressionvalidator controltovalidate="txtPassword" display="Dynamic" errormessage="&lt;i&gt;The string must be 20 characters or less...&lt;/i&gt;" runat="server" validationexpression="^.{1,20}$"></asp:regularexpressionvalidator>
 6<br/>
 7<asp:button onclick="DisplayEncryptedText" runat="server" text="View the String as Encrypted Text"></asp:button>
 8<p>
 9<asp:literal id="ltlResults" runat="server"></asp:literal>
10</p></form>