ConfigurationElement set null default value

Question

I have a small problem with a custom configuration section in App.config. The problem is: I have a CustomElement (let's call it 'a') whose properties CustomElement another (let's call it 'b').

I would like to have b as a value not null only if specified as a secondary element.

Eg

In this case, I have a b as not null, and that's ok.

<a prop_a1="" prop_a2="">
    <B prop_b1 = "" />
</ A>

But, in the following case, b should be null, but it is not.

<a prop_a1="" prop_a2="" />

Is it possible to have a null value in case 2?

Thanks to all those who want to help me.

public class Cfg : ConfigurationElement
{
        [ConfigurationProperty("prop", IsRequired = true)]
        public ErrorCfg Prop
        {
            get { return (string)this["prop"]; }
            set { this["prop"] = value; }
        }
}

public class ErrorCfg : ConfigurationElement
{
    [ConfigurationProperty("prop1", IsRequired = true)]
    public string Prop1
    {
        get { return (string)this["prop1"]; }
        set { this["prop1"] = value; }
    }

    [ConfigurationProperty("prop2", IsRequired = true)]
    public string Prop2
    {
        get { return (string)this["prop2"]; }
        set { this["prop2"] = value; }
    }
}

if (_cfgItem.ErrorCfg != null)
{....}

In this case ErrorCfg is not null, but Prop1 and Pro2 are empty string

In the 2nd example what value is b? And post the code how you get the values for a small verifiable example — EpicKip, Apr 19 '17 at 11:16

score 1 · Answer 1 · answered Feb 18 '20 at 14:46

1

I think this is not possible. But you can find out if the ConfigurationElement is present in the configuration file:

if (_cfgItem.ErrorCfg.ElementInformation.IsPresent)
{....}

answered Feb 18 '20 at 14:46

Stefan Bormann

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ConfigurationElement set null default value

1 Answers1