aspnet_regiis -pef section web-app-physical-dir
Encrypt the configuration section. Optional arguments:
[-prov provider] Use this provider to encrypt.
aspnet_regiis.exe -pef "connectionStrings" "C:\myweb\HelloService"
aspnet_regiis.exe -pef "appSettings" "C:\myweb\HelloService"
<?xml version="1.0"?>
<configuration>
<system.web>
<compilation targetFramework="4.0" />
</system.web>
<connectionStrings configProtectionProvider="RsaProtectedConfigurationProvider">
<EncryptedData Type="http://www.w3.org/2001/04/xmlenc#Element"
xmlns="http://www.w3.org/2001/04/xmlenc#">
<EncryptionMethod Algorithm="http://www.w3.org/2001/04/xmlenc#tripledes-cbc" />
<KeyInfo xmlns="http://www.w3.org/2000/09/xmldsig#">
<EncryptedKey xmlns="http://www.w3.org/2001/04/xmlenc#">
<EncryptionMethod Algorithm="http://www.w3.org/2001/04/xmlenc#rsa-1_5" />
<KeyInfo xmlns="http://www.w3.org/2000/09/xmldsig#">
<KeyName>Rsa Key</KeyName>
</KeyInfo>
<CipherData>
<CipherValue>E2fO9C0TJVxImLYQZza+fCQdDbTpNh/kOKLRsK6zcFjkgtUCl6SnMViuu/2G1NVTxqXyEWYwyK6AiCZA+feeG/AvYvmEEVopVDb0YyGeuJgEI1r8HxTl8Cv+f2EIimP7LJI+JRZVerI4MU6Ke3wxm2S/ATc73/W6eg9808f4/D6J0pp3wND4E79gBiAnBHFYQIefdJYUsmHR9z9LiIqjCllkkj/JB0kso0kGJ9i+iew1Jae5jugIN8gPxsXbCfmw6ru3I3Kbpa8Z5AllfkFA2YKrsuV3c7eLLJ0kB4lsIJIUTy3kRyA4GjdChOmlNwwffIbhwUPPxa25CiF0VAq27Q==</CipherValue>
</CipherData>
</EncryptedKey>
</KeyInfo>
<CipherData>
<CipherValue>I1DWG11Iz/rq+NC9C/21B3Q22J9+IexHPH6kkWvQPeHUO6OvOWeQbk3wHALR2ql8pz0gQJFyfTypMk/xSSikFI2Dcy5mgYY3kP73bQQ83ho3O1HPw9TsRtK1G8gmVNGyQLj7iTRcoGfiYYmSibPynv1MzSV1qDXlnVfKiMqKRZ5ZPiMSMc5u3dDEL/JW1oCvAGs5tHrZU5+vgvm0yCmSuCWZbXva+iv9J35EQqs58pq+hwVo1hg1dffdupGCBykaXGl5VX3TIGc=</CipherValue>
</CipherData>
</EncryptedData>
</connectionStrings>
<appSettings configProtectionProvider="RsaProtectedConfigurationProvider">
<EncryptedData Type="http://www.w3.org/2001/04/xmlenc#Element"
xmlns="http://www.w3.org/2001/04/xmlenc#">
<EncryptionMethod Algorithm="http://www.w3.org/2001/04/xmlenc#tripledes-cbc" />
<KeyInfo xmlns="http://www.w3.org/2000/09/xmldsig#">
<EncryptedKey xmlns="http://www.w3.org/2001/04/xmlenc#">
<EncryptionMethod Algorithm="http://www.w3.org/2001/04/xmlenc#rsa-1_5" />
<KeyInfo xmlns="http://www.w3.org/2000/09/xmldsig#">
<KeyName>Rsa Key</KeyName>
</KeyInfo>
<CipherData>
<CipherValue>WVoFIs8rSEgqKw1C0QCmePs7WK6EIoGCfdx9CTJNmABoVvoEWPnOEQwz/6Ruu0rGwa7q91KuhGILmy4NEN0padnX6FScCdEzP6CS59U3IFumYmTrD7D9ihqFO2aIL/SuBvV3D2kxhHaYGFaPuvYgsyOLf3+aYR3O/uh/k5wZxLoIeKUUrT762J3bdaK6cJWQeuOu4j2vDXEdawdwhlnK12UV8+/AXZNlFW1N3Z0RUVFX1nMSwTaIu8F3tZ9hCFbGwbTm2T0XnfDOcB6dCxCutqC8pXD36laAfiSANzAWoC+Yhf5eFSj24fX0NU6UTQB8fqLyOgWsIMLxZLKVrwnlmg==</CipherValue>
</CipherData>
</EncryptedKey>
</KeyInfo>
<CipherData>
<CipherValue>5W2KhG/oETLUDptobcOM52x1qD/g9A0By/wcGXI+fm7EdcD8mT3TxsLVBVcHRBCyUO7OIHl8NyCrduRSYwyd8ggBCriQ5KrbAmW4LXrNnw/JjjCEJWPuRcRucVRfpgap2nHh6BXRXC/AU6v0GcRqy7LV8179PgGtyAa8IE1mV/w=</CipherValue>
</CipherData>
</EncryptedData>
</appSettings>
</configuration>
其中RSAProtectedConfigurationProvider是默认的缺省provider，如果想使用DPAPIProtectedConfigurationProvider，可以用-prov参数指明：
aspnet_regiis.exe -pef "connectionStrings" "C:\myweb\HelloService" -prov "DataProtectionConfigurationProvider"
aspnet_regiis.exe -pef "appSettings" "C:\myweb\HelloService" -prov "DataProtectionConfigurationProvider"
加密配置文件后，源程序不需要做任何改动。如果要修改或添加新的配置信息，需要先解密配置文件。不论使用哪种Provider，都只能在进行加密的计算机上对配置文件进行解密。
-pdf section web-app-physical-dir
Decrypt the configuration section.
aspnet_regiis.exe -pdf "connectionStrings" "C:\myweb\HelloService"
aspnet_regiis.exe -pdf "appSettings" "C:\myweb\HelloService"
配置文件中经常会有用户名密码的敏感信息，为了防止该信息泄露，需要对配置文件进行加密。加密与解密可以使用.NET提供的工具aspnet_regiis.exe，可以在Windows .NET的文件夹中找到它。
该工具只对web.config文件进行修改，如果要加密或解密app.config，可以先将app.config文件改名为web.config，加密或解密后再改回来。