Question

我有一个现有的ASP.NET项目，其中通过在C＃中使用自定义加密函数在Web.config文件中加密连接字符串，并将该加密字符串保存到Web.config文件中，如下所示......

<add name="ConnectionString" connectionString="+tj/H0V/Wpa+UBWzHvOfuL4GPyoDssypPKfeRdUU1FnfHw+phOEBLpRne/ytv1v8gs7P0DoSC7rhN2aPWG3uZZvSis5f/Dqu53HgsRH8m44=" providerName="System.Data.SqlClient" />

我现在想要使用需要SQLDataSource的控件向该项目添加一个Page，并且我已经在.aspx代码中指定了ConnectionString，作为SQLDataSource的属性，如下所示......

<asp:SqlDataSource ID="PeriodsDataSource" runat="server" ConnectionString="<%$ ConnectionStrings:ConnectionString %>"

这显然现在正在尝试读取connectionString，但是获取加密字符串，并抛出错误......

“不支持关键字： '+ TJ / h0v / WPA + ubwzhvoful4gpyodssyppkferduu1fnfhw + phoeblprne / ytv1v8gs7p0dosc7rhn2apwg3uzzvsis5f / dqu53hgsrh8m44'。“

如何将ConnectionString传递给我的自定义Encryption.Decrypt函数，以便SQLDataSource使用Un-Encrypted字符串？

我试过简单地将以下内容添加到Page_Load事件中，这有助于初始加载，但在回发后我仍然得到上面提到的错误。（不，这不在！IsPostBack中）

string connectionString = Encryption.Decrypt(ConfigurationManager.ConnectionStrings["ConnectionString"].ConnectionString, "XXXXXX");
        PeriodsDataSource.ConnectionString = connectionString;

Answer 1

这是我已实施的解决方案。

%$中ConnectionString的{{1}}字符是一个表达式，因此被求值。我们可以创建自己的自定义表达式。

像这样创建asp:SqlDataSource并扩展class

ExpressionBuilder

您已经在namespace YourNameSpace { [ExpressionPrefix("EncryptedExpressionStrings")] public class EncryptedConnectionStringExpressionBuilder : ExpressionBuilder { private static string DecryptConnectionString(string cipherText) { return Encryption.Decrypt(cipherText); } public static ConnectionStringSettings GetConnectionStringSettings(string connectionStringName) { return ConfigurationManager.ConnectionStrings[connectionStringName]; } public static string GetConnectionString(string connectionStringName) { string decryptedConnectionString = null; System.Web.Caching.Cache connectionStringCache = new System.Web.Caching.Cache(); if (connectionStringCache["connectionString"] == null) { ConnectionStringSettings settings = GetConnectionStringSettings(connectionStringName); decryptedConnectionString = DecryptConnectionString(settings.ConnectionString); connectionStringCache.Insert("connectionString", decryptedConnectionString); } else { decryptedConnectionString = (string)connectionStringCache["connectionString"]; } return decryptedConnectionString; } public static string GetConnectionStringProviderName(string connectionStringName) { ConnectionStringSettings settings = GetConnectionStringSettings(connectionStringName); return settings.ProviderName; } public override CodeExpression GetCodeExpression(BoundPropertyEntry entry, object parsedData, ExpressionBuilderContext context) { Pair pair = DirectCast<Pair>(parsedData); string text = pair.First.ToString(); if (Convert.ToBoolean(pair.Second)) { return new CodeMethodInvokeExpression(new CodeTypeReferenceExpression(base.GetType()), "GetConnectionString", new CodeExpression[] { new CodePrimitiveExpression() { Value = text } }); } else { return new CodeMethodInvokeExpression(new CodeTypeReferenceExpression(base.GetType()), "GetConnectionStringProviderName", new CodeExpression[] { new CodePrimitiveExpression() { Value = text } }); } static T DirectCast<T>(object o) where T : class { T value = o as T; if (value == null && o != null) { throw new InvalidCastException(); } return value; } }

中声明了新的自定义ExpressionBuilder

web.config

然后您声明已加密的connectionString

<compilation>
    <expressionBuilders>
        <add expressionPrefix="EncryptedExpressionStrings" type="YourNameSpace.EncryptedConnectionStringExpressionBuilder"/>
     </expressionBuilders>
</compilation>

然后，在web.config中为自定义<connectionStrings> <add name="EncryptedSqlDBConnectionString" connectionString="nWCfxsad8lkdyLWERODVxd3Ox..." </connectionStrings>声明前缀的名称，并在ExpressionBuilder中声明ConnectionString的名称

asp:SqlDataSource

这意味着您可以在<asp:SqlDataSource runat="server" ID="YourID" ConnectionString="<%$ EncryptedExpressionStrings:EncryptedSqlDBConnectionString %>" SelectCommand="SELECT * FROM YourDBTable" />中加密连接字符串，并且仍然可以评估web.config asp.SqlDataSource。

Answer 2

事实证明，这是更新SqlDataSource的Init事件中SqlDataSource.ConnectionString的非常简单的解决方案，如下所示：

    protected void SqlDataSource_Init(object sender, EventArgs e)
    {
        string connectionString = Encryption.Decrypt(ConfigurationManager.ConnectionStrings["ConnectionString"].ConnectionString, "XXXXXX");
        SqlDataSource.ConnectionString = connectionString;
    }

从Web.config中读取自定义加密连接字符串

2 个答案: