c# - Why instance variable's value are changed as per function values -

i have class. have 2 instance member variables x , y, , class has function again takes 2 variables named x , y.

public class myclass {     public int x;     public int y;      public int add(int x , int y)     {         return (x + y);     } } 

now creating instance of class , assigning values instance variables , if call function using same instance value of instance variables getting changed values passing parameter function shown below

        myclass abs = new myclass();         abs.x = 10;         abs.y = 11;         console.writeline(abs.add(12, 13).tostring()); 

while debugging found value of instance variables changed 12 , 13 respectively. why so? happening.

i'm sure instance fields not changed. misinterpreted debugger output. if watch x or y while in add method debugger (watch window) show values of method parameters. need watch this.x or this.y.

that's 1 of reasons why start instance fields underscore.