The ToString () method output alert () and Console.log () in the JavaScript prototype chain have different results

2. <script language="JavaScript">
   
4. function myObj() {
   
6. var total = 0;
   
8. }
   
10. MYOBJ. Prototype. Add = function(a,b) {
    
12. this. Total = a + b;
    
14. }
    
16. MYOBJ. Prototype. toString = function() {
    
18. return this . Total;
    
20. }
    
24. var obj = new myObj();
    
26. Obj. Add(1,2);
    
28. Console.  Log(obj); //The output here is MyObj
    
30. Alert(obj); //The output result here is 3
    
32. </Script>

Reason:

Console.log () can print any type of data. Alert () can only output a string if the alert output is an object that automatically calls the ToString () method. If you want the Console.log () output to be the same as alert, you need to call ToString ():

Console.log (Obj.tostring ());

The ToString () method output alert () and Console.log () in the JavaScript prototype chain have different results