Arduino 扩展库的制作（官网原文件精细翻译）-附详细实例...

First, make a Morse directory inside of the libraries sub-directory of your sketchbook directory.Copy or move the Morse.h and Morse.cpp files into that directory.Now launch the Arduino
environment.If you open the Sketch > Import Library menu, you should see Morse inside.The library will be compiled with sketches that use it.If the library doesn't seem to build, make sure thatthe files really end in .cpp and .h (with no extra .pde or .txt extension, for example).
　　首先，在扩展库的子目录建一个莫尔斯扩展库目录。把Morse.h和Morse.cpp文件复制或移动到该目录中。现在打开Arduino编译器。打开“Sketch”>“Import Library”菜单，你应该看到有“Morse”选项。在使用的时候该扩展库将同时被编译。如果没有看到这个扩展库，请确保文件名为正常的“.cpp”和“h”（没有其它多余的如“.pde”或“.txt”这样的扩展名）。

Let's see how we can replicate our old SOS sketch using the new library:
　　让我们看看现在我们怎样用新的扩展库来编写我们的原先的程序： #include <Morse.h>Morse morse(13);void setup(){}void loop(){morse.dot(); morse.dot(); morse.dot();morse.dash(); morse.dash(); morse.dash();morse.dot(); morse.dot(); morse.dot();delay(3000);}复制代码
There are a few differences from the old sketch (besides the fact that some of the code has moved to a library).
　　除了将一些代码已经转移到扩展库里，这些代码有些差别。
First, we've added an #include statement to the top of the sketch.This makes the Morse library available to the sketch and includes it in the code sent to the board.That means if you no longer need a library in a sketch, you should delete the #include statement to save space.
　　首先，我们仅需要在代码顶部添加#include语句，就可以使程序使用这个扩展库，并且在编译时会被同时编译进去。这也意味着你在程序中不需要再编写长长的代码。而且如果你不再需这个功能，只要删除这个“#include”语句就可以了。
Second, we now create an instance of the Morse class called morse :
现在，我们来创建一个莫尔斯类的过程：
Morse morse(13);
When this line gets executed (which actually happens even before the setup() function), the constructor for the Morse class will be called, and passed the argument you've given here (in
this case, just 13 ).
　　当此行被执行时（实际上它在setup()函数执行之前就已经被执行了），将引用“Morse”类（本例子中使用针脚13）。
Notice that our setup() is now empty; that's because the call to pinMode() happens inside the library (when the instance is constructed).
　　请注意，在这里“void setup()”是空的，这是因为“pinMode()”的调用发生在扩展库中（在调用函数的时候）。
Finally, to call the dot() and dash() functions, we need to prefix them with morse. - the name of the instance we want to use.We could have multiple instances of the Morse class, each on their own pin stored in the _pin private variable of that instance.By calling a function on a particular instance, we specify which instance's variables should be used during that call to a
function.That is, if we had both:
　　最后，调用“dot()”和“dash()”函数时，我们需要用“morse”作它们的的前缀。程序中我们可以多次引用，它们每个的针脚数据都储存在“_pin”私有变量里。我们可以定义多个“Morse”类的函数，每一个都有自己的“_pin”私有变量。在某过个程中调用函数时，我们可以指定的不同的针脚变量，这些私有变量都仅是在函数调用过程中被使用。也就是说，如果我们有两次调用： Morse morse(13);Morse morse2(12);复制代码
then inside a call to morse2.dot() , _pin would be 12.
　　后面的私有变量“_pin”将会是针脚12 。