考虑下面的java代码。

public class Test{
   public String hello(String name){
      return "Hello Mr."+name;
   }

  public static void main(String args[]){
     Test test = new Test();
     String myName = "James Bond";
     test.hello(myName);
  }
}

hello(String name)的方法定义声明了一个名为name的String参数。 在main方法中，我们通过传入参数myName来调用hello方法。

parameter是占位符，而argument是方法的实际值。

假设你是一家航空公司。你造了一架飞机。你在里面安装座椅。然后，你把飞机装满乘客，然后把它送到某个地方。乘客们下了船。第二天，你再次乘坐同一架飞机，同样的座位，但这次乘客不同。

平面是你的函数。

参数是座位。

争论的焦点是坐在座位上的乘客。

function fly(seat1, seat2) {
    seat1.sayMyName();
    // Estraven
    seat2.sayMyName();

    etc.
}

var passenger1 = "Estraven";
var passenger2 = "Genly Ai";

fly(passenger1, passenger2); 

参数和参数

All the different terms that have to do with parameters and arguments can be confusing. However, if you keep a few simple points in mind, you will be able to easily handle these terms. The formal parameters for a function are listed in the function declaration and are used in the body of the function definition. A formal parameter (of any sort) is a kind of blank or placeholder that is filled in with something when the function is called. An argument is something that is used to fill in a formal parameter. When you write down a function call, the arguments are listed in parentheses after the function name. When the function call is executed, the arguments are plugged in for the formal parameters. The terms call-by-value and call-by-reference refer to the mechanism that is used in the plugging-in process. In the call-by-value method only the value of the argument is used. In this call-by-value mechanism, the formal parameter is a local variable that is initialized to the value of the corresponding argument. In the call-by-reference mechanism the argument is a variable and the entire variable is used. In the call- by-reference mechanism the argument variable is substituted for the formal parameter so that any change that is made to the formal parameter is actually made to the argument variable.

来源:绝对的c++， Walter Savitch

也就是说,

或者更简单…

争论开始了!

参数输出!

参数是函数定义中的变量 参数是参数的值

<?php

    /* define function */
    function myFunction($parameter1, $parameter2)
    {
        echo "This is value of paramater 1: {$parameter1} <br />";
        echo "This is value of paramater 2: {$parameter2} <br />";
    }

    /* call function with arguments*/
    myFunction(1, 2);

?>

当我们在Java中创建方法(函数)时，方法是这样的..

方法的数据类型名称(Data-type variable-name)

在括号中，这些是形参，当我们调用方法(函数)时，我们传递这个形参的值，这些值称为实参。