javascript--functions-Passing by value

Pass-by-value (byvalue): When you assign a value between two variables or pass a variable as an argument to a function, the value in the original variable is assigned to the other party (the new variable).
Value for Primitive type: Modify new variable without affecting the original variable
object to reference type: Modifying an object with a new variable is equivalent to modifying the original object directly.

First example: Values of the original type

1     var a=10; 2     var b=a; // Take out the value in a and copy one to B. 3     a++; 4     Console.log (a); //  One 5     Console.log (b); // Ten

Second example: Objects of a reference type

1. Functions

1     var card=10; 2     function Buy (Card) {3       card-=3; 4       Console.log (card); 5     }6     Buy (card);   77     console.log (card);   Ten

2. Arrays

1     varmy=["Package", "Package", "Package", "Package", "package"];2          //0 1 2) 3 43     varIpxmy;4Lp[0]= "";5Console.log (String (my));//46My[4]= "";7Console.log (String (LP));//38 9     vararr=[1,2,3,4,5];Ten            //0 1 2) 3 4 One     functionFun (arr) { AArr[5]=6; -arr=[1,2,3]; -Arr[6]=12; the Console.log (arr); -     } -Fun (arr);//123,,, -Console.log (arr);//123456

javascript--functions-Passing by value