可以说这是您的连接字符串：

<connectionStrings>
    <add name="cs" connectionString="Data Source=myServerAddress;Initial Catalog=myDataBase;User Id=myUsername;Password=XXSDFASFDKSFJDKLJFDWERIODFSDFHSDJHKJNFJKSD;"/>
</connectionStrings>

然后，您可以执行以下操作：

string myCs = System.Configuration.ConfigurationManager.ConnectionStrings["cs"].ConnectionString;

System.Data.SqlClient.SqlConnectionStringBuilder csb = new System.Data.SqlClient.SqlConnectionStringBuilder(myCs);
csb.Password = EncDecHelper.Decrypt(csb.Password);
myCs = csb.ToString();

您可以EncDecHelper.Decrypt使用以下示例编写：加密和解密字符串