By using implicit and operator overloading, you can think of a kind of fool writing method that specifically deals with forced = ture, or cannot contain = true.

In this post, system. there is still some debate about the code style message about convert. I wonder if I can make the behavior of IF (OBJ) And if (OBJ = ture) Different? I tried it.

For example, the following code

1 static void main (string [] ARGs)
2 {
3 var confusedvalue = getvalue ();
4
5 If (confusedvalue = true)
6 {
7 console. writeline ("confusedobj = true ");
8}
9
10 if (confusedvalue)
11 {
12 console. writeline ("implicit conversion confusedobj = true ");
13}
14
15 if (! Confusedvalue)
16 {
17 console. writeline ("implicit conversion confusedobj = false ");
18}
19}

Intuitively, we must think that if (confusedvalue = true) And if (confusedvalue) are the same. Otherwise, the actual running result is as follows:

 1     public class ConfusedClass
 2     {
 3         public static bool operator == (ConfusedClass left, bool right)
 4         {
 5             return right;
 6         }
 7 
 8         public static bool operator !=(ConfusedClass left, bool right)
 9         {
10             return !right;
11         }
12 
13         public static implicit operator bool(ConfusedClass obj) 
14         {
15             return false;
16         }
17 
18         public override bool Equals(object obj)
19         {
20             return base.Equals(obj);
21         }
22     }

 

I briefly explained this class. First, I overloaded the operators = and! =, So when confusedvalue = true, the fourth line is actually executed ~ Six rows of functions. Then, I used the implicit keyword, which is used to declare an implicit user-defined type conversion operator. In this way, when the confusedclass instance is implicitly converted to bool, in any case, false is returned.

If you want to make trouble, This is a method. For example, if (confusedvalue) is normal, but your project manager specifies that the Code style must be if (confusedvalue = true), you can set a trap, if someone else uses the IF (confusedvalue = true) method to write your code or use your class, the opposite is true. And vice versa.

Finally, I don't want to be confused. For example, if I had the Rewiew code and encountered implicit type conversion, I must delete it. However, implicit keywords are rare.