D（编程语言）/d2/函数简介

第3课：函数简介

在本课中，您将更多地了解函数，这些函数在第1课中已使用过。如果您已经熟悉其他类似C的语言，则只需略读即可。

入门代码

import std.stdio;

int watch_tv(int first_watched, int then_watched, string channel = "The PHBOS Channel")
{
    writefln("Finished watching %s.", channel);
    return first_watched + then_watched;
}

int commercials(int minutes)
{
    writefln("Watching %s minutes of commercials.", minutes);
    return minutes;
}

int cartoons(int minutes)
{
    writefln("Watching %s minutes of cartoons.", minutes);
    return minutes;
}

void main()
{
    auto minutesoftv = watch_tv(commercials(10), cartoons(30));
    writeln(minutesoftv, " minutes of TV watched!");
}

/*
Output:
  Watching 10 minutes of commercials.
  Watching 30 minutes of cartoons.
  Finished watching The PHBOS Channel.
  40 minutes of TV watched!
*/

概念

函数

函数允许您编写更有条理的代码。使用函数，您可以编写一些代码一次，然后在需要使用该代码时随时调用它。

函数语法

让我们看一下语法

return_type name_of_function(arg1type arg1, arg2type arg2)
{
    // function body code here
    return something;
}