.NET Application Settings & # 8594; zero line setting

Question

What should I enter (in both cases) in the appSettings section of the app.config application so that when reading the settings I can get the following:

• Settings .Default.FooString == null
• Settings .Default.FooString == string.Empty

? I think there is no way to achieve both situations, or am I missing something?

Eliminate the need for whether the string value is zero or empty, because this value goes to another system, which makes different decisions on these two. thank

---

Additional Information:

The .Designer.cs settings are regenerated every time you change the settings tab. Generated Sample:

    [global::System.Configuration.UserScopedSettingAttribute()]
    [global::System.Diagnostics.DebuggerNonUserCodeAttribute()]
    [global::System.Configuration.DefaultSettingValueAttribute("")]
    public string Foo {
        get {
            return ((string)(this["Foo "]));
        }
        set {
            this["Foo "] = value;
        }
    }

[DefaultSettingValueAttribute ("")]. , , [DefaultSettingValueAttribute (null)], , .

?

Answer 1

, , null != String.Empty.

Boolean String.IsNullOrEmpty(String) .

Answer 2

appSetting undefined, null, value = "", , String.Empty

Answer 3

a null <value />.

a string.Empty <value /> <value></value>.