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POHow to retrieve a child class instance as sender in its base class event args?
 

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  1. POHow to retrieve a child class instance as sender in its base class event args?
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    <p>I have a class called <code>DataModel</code> that implements the <code>INotifyDataErrorInfo</code> interface. In my app all my Models inherit from this app so that I don't have to code error handling logic nor change notification in any other classes. How can I raise the base class event below but send the child class that called it as a sender? I want to minimize repetitive code and would wish to avoid the whole virtual and override scenario.</p> <pre><code>virtual void SetErrors(string propertyName, List&lt;string&gt; propertyErrors) { //clear any errors that already exist for this property errors.Remove(propertyName); //add the list of errors for the specified property errors.Add(propertyName, propertyErrors); //raise the error notification event if (ErrorsChanged != null) ErrorsChanged(this, new DataErrorsChangedEventArgs(propertyName)); } </code></pre> <h2>Edit- Question is not clear enough</h2> <p>For example say I have this class</p> <pre><code>public class GangMember : Models.Base_Classes.DataObject { int _age; public int Age { set { _age = value; if (value &lt; 0) { List&lt;string&gt; errors = new List&lt;string&gt;(); errors.Add("Age can not be less than 0."); SetErrors("Age", errors); } } } } </code></pre> <p>When <code>SetErrors()</code> is called in my base class <code>DataModel</code> it raises it's event <code>ErrorsChanged</code> and passes it an instance of itself <code>this</code>. How can I get a reference to the child class <code>GangMember</code> in this situation?</p>
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    1. USRomoku
    1. USAdrian
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    1. COnot sure what you're asking, if you need to pass the type of the child class just use `this.GetType()` because it comes off the instance it pulls the child class, not the parent.
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      1. USMgetz
    2. COActually, the base class can also use `this.GetType()` and it will still get the child class type as a result. So you don't even need to pass it as a parameter.
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      1. USJon
    3. CO@Jon so in the scenario I put above, it will return my `GangMember` class? I thought the keyword `this` always returned a reference to the executing class in which case would be the base class?
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      1. POHow to retrieve a child class instance as sender in its base class event args?
      1. USAdrian
 

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