首先添加引用:

using System.Web.Configuration;

加密操作如下:

private void ProtectSection(string sectionName, string provider)
{
Configuration config =
WebConfigurationManager.
OpenWebConfiguration(Request.ApplicationPath);

ConfigurationSection section = config.GetSection(sectionName);

if (section != null && !section.SectionInformation.IsProtected)
{
section.SectionInformation.ProtectSection(provider);
config.Save();
}
}

解密操作如下:

private void UnProtectSection(string sectionName)
{
Configuration config =
WebConfigurationManager.
OpenWebConfiguration(Request.ApplicationPath);
ConfigurationSection section = config.GetSection(sectionName);
if (section != null && section.SectionInformation.IsProtected)
{
section.SectionInformation.UnprotectSection();
config.Save();
}
}

实践:
加密前的配置文件:

加密后的配置文件:

AQAAANCMnd8BFdERjHoAwE/Cl+s
BAAAABi1ATlNkEUGEf0XyWGL2Xg
QAAAACAAAAAAADZgAAqAAAABAAA
ABIhxMWlazAntwIIpST1CDXAAAA
AASAAACgAAAAEAAAAPz/YKYx07c
b+h4fqdr4fkLgAAAAX1Ieyc+WSx
AfsDW1vn2C/fXsG2TAnYeUgaCov
8e3nGFTHHsH91gLiqKregFPYzGR
vW1xrez/3VwOmJI9eS7EFKrcXej
NnHL66kg2iNRk3ntLNZlZtTs3cZ
9w63u47VKAjs6miWsGBz2GntL/9
UGHLELigrJcr3YJ+lsjOscExQnv
HGvA48EfxpD+tEiFBtgXeHsFkQX
cqGySshx16vCt2GUNUC3ZmEAhBh
UsAFkPIYqelYHd4+m9a/xPe2tqw
GIbla1wbW2NDEfrzJPwnkfmpNqR
hXijKImipwXbDVYy6o0UAAAAs8D
suYNOhJ7qAjJa2c/4eUC7sks=

来源:网络