c# - Why I am getting null exception when using an Interface -

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• what nullreferenceexception, , how fix it? 33 answers

public class blah {     public bool whatever { get; set; }     public string whatyoujustsaid { get; set; } }  public interface iblah {     blah blahvalues { get; set; } }  class class1:iblah {     public blah blahvalues { get; set; } } 

and example:

   class1 c1 = new class1();    c1.blahvalues.whatyoujustsaid = "nothing";     c1.blahvalues.whatever = false; 

so how should change code blahvalues doesn't null?

you have initialize blahvalues. using object initializer, can done below:

class1 c1 = new class1() {    blahvalues = new blah()  }; 

as create c1 object, blahvalues it's default value, null. hence, when try assign value whatyoujustsaid , whatever null reference exception.