查看“Micro:bit系列教程11：板载应用”的源代码



<span style="font-size:12.0pt;line-height:150%;font-family:宋体;mso-ascii-theme-font:
minor-fareast;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;
mso-hansi-theme-font:minor-fareast">本章将介绍Micro:bit的板载应用，主要包括：图像、文本、数学、游戏。


<h1 style="line-height:150%"><span lang="EN-US" style="font-size:15.0pt;
line-height:150%;font-family:黑体;font-weight:normal;mso-bidi-font-weight:bold">1.<span style="font-size:15.0pt;line-height:150%;font-family:黑体;font-weight:normal;
mso-bidi-font-weight:bold">图像

</h1>

      <span lang="EN-US" style="font-size:
12.0pt;line-height:150%;font-family:宋体;mso-ascii-theme-font:minor-fareast;
mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-theme-font:
minor-fareast">Micro:bit<span style="font-size:12.0pt;line-height:150%;
font-family:宋体;mso-ascii-theme-font:minor-fareast;mso-fareast-font-family:宋体;
mso-fareast-theme-font:minor-fareast;mso-hansi-theme-font:minor-fareast">可通过5x5点阵作为屏幕进行相关符号的显示，但对于篇幅较大的符号，可采取分两屏滚动显示的策略。



<span lang="EN-US" style="font-size:
12.0pt;line-height:150%;font-family:宋体;mso-ascii-theme-font:minor-fareast;
mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-theme-font:
minor-fareast">  <span style="font-size:12.0pt;line-height:150%;font-family:宋体;mso-ascii-theme-font:
minor-fareast;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;
mso-hansi-theme-font:minor-fareast">下面，将通过例程来说明Micro:bit图像的使用,打开makecode，采用积木块的方式编写以下程序:




[[File:135808d37k6iy34ye7exi6.png]]


<span lang="EN-US" style="font-size:
12.0pt;line-height:150%;font-family:宋体;mso-ascii-theme-font:minor-fareast;
mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-theme-font:
minor-fareast">  <span style="font-size:12.0pt;line-height:150%;font-family:宋体;mso-ascii-theme-font:
minor-fareast;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;
mso-hansi-theme-font:minor-fareast">在该积木块程序中，首先，将arrows变量设定为创建的大图，在开机无限循环中，将arrows变量定义的图像每隔500ms向左移动1格，当一幅图像偏移完成后，又从头开始进行偏移，下载到Micro:bit可观察该现象。



<span lang="EN-US" style="font-size:
12.0pt;line-height:150%;font-family:宋体;mso-ascii-theme-font:minor-fareast;
mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-theme-font:
minor-fareast">  <span style="font-size:12.0pt;line-height:150%;font-family:宋体;mso-ascii-theme-font:
minor-fareast;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;
mso-hansi-theme-font:minor-fareast">在下面的例程中，将说明其它几个积木块的使用方法，打开makecode，采用积木块的方式编写以下程序：




[[File:135809bm8d20rdm0rdp82n.png]]


<span lang="EN-US" style="font-size:
12.0pt;line-height:150%;font-family:宋体;mso-ascii-theme-font:minor-fareast;
mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-theme-font:
minor-fareast">  <span style="font-size:12.0pt;line-height:150%;font-family:宋体;mso-ascii-theme-font:
minor-fareast;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;
mso-hansi-theme-font:minor-fareast">在该积木块程序中，将arrows变量设定为创建的大图，在无限循环中，一直显示将向左箭头向左偏移2格的图像，下载到Micro:bit可观察该现象。



<span lang="EN-US" style="font-size:
12.0pt;line-height:150%;font-family:宋体;mso-ascii-theme-font:minor-fareast;
mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-theme-font:
minor-fareast">  <span style="font-size:12.0pt;line-height:150%;font-family:宋体;mso-ascii-theme-font:
minor-fareast;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;
mso-hansi-theme-font:minor-fareast">此外，还可以获取箭头图像，图标图像，以及箭头图像对应的数字。



<span style="font-size:12.0pt;
line-height:150%;font-family:宋体;mso-ascii-theme-font:minor-fareast;mso-fareast-font-family:
宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-theme-font:minor-fareast">获取箭头图像:




[[File:135809xahcch74g7thwctc.png]]


<span style="font-size:12.0pt;
line-height:150%;font-family:宋体;mso-ascii-theme-font:minor-fareast;mso-fareast-font-family:
宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-theme-font:minor-fareast">获取图标图像:




[[File:135809qoysotczeihedb2z.png]]


<span style="font-size:12.0pt;
line-height:150%;font-family:宋体;mso-ascii-theme-font:minor-fareast;mso-fareast-font-family:
宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-theme-font:minor-fareast">获取箭头图像对应的数字：




[[File:135810l0u0aeaowqvoehxa.png]]

<h1 style="line-height:150%"><span lang="EN-US" style="font-size:15.0pt;
line-height:150%;font-family:黑体;font-weight:normal;mso-bidi-font-weight:bold">2.<span style="font-size:15.0pt;line-height:150%;font-family:黑体;font-weight:normal;
mso-bidi-font-weight:bold">文本

</h1>

<span lang="EN-US" style="font-size:12.0pt;font-family:宋体;mso-ascii-theme-font:minor-fareast;
mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-theme-font:
minor-fareast">Micro:bit<span style="font-size:12.0pt;font-family:宋体;
mso-ascii-theme-font:minor-fareast;mso-fareast-font-family:宋体;mso-fareast-theme-font:
minor-fareast;mso-hansi-theme-font:minor-fareast">提供了一系列字符串方法对应的积木块，下面来分别介绍相应的积木块：


<h2><span lang="EN-US" style="font-size:12.0pt;line-height:173%;font-family:宋体;
mso-ascii-theme-font:minor-fareast;mso-fareast-theme-font:minor-fareast;
mso-hansi-theme-font:minor-fareast">2.1 <span style="font-size:12.0pt;
line-height:173%;font-family:宋体;mso-ascii-theme-font:minor-fareast;mso-fareast-theme-font:
minor-fareast;mso-hansi-theme-font:minor-fareast">创建字符串

</h2>


[[File:135810tzek8ttyb1ey1att.png]]


      <span style="font-size:12.0pt;
line-height:150%;font-family:宋体;mso-ascii-theme-font:minor-fareast;mso-fareast-font-family:
宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-theme-font:minor-fareast">通过该积木块创建对应的字符串，支持ASCII 32-126对应的字符，数字，标点符号和其它一些符号将在屏幕(LED点阵)上面显示为“？”。


<h2><span lang="EN-US" style="font-size:12.0pt;line-height:173%;font-family:宋体;
mso-ascii-theme-font:minor-fareast;mso-fareast-theme-font:minor-fareast;
mso-hansi-theme-font:minor-fareast">2.2 <span style="font-size:12.0pt;
line-height:173%;font-family:宋体;mso-ascii-theme-font:minor-fareast;mso-fareast-theme-font:
minor-fareast;mso-hansi-theme-font:minor-fareast">获取文本的长度

</h2>


[[File:135810uvt2rkscvsstrksa.png]]


      <span style="font-size:12.0pt;font-family:宋体;mso-ascii-theme-font:minor-fareast;
mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-theme-font:
minor-fareast">通过该积木块，可获得字符串的长度。


<h2><span lang="EN-US" style="font-size:12.0pt;line-height:173%;font-family:宋体;
mso-ascii-theme-font:minor-fareast;mso-fareast-theme-font:minor-fareast;
mso-hansi-theme-font:minor-fareast">2.3 <span style="font-size:12.0pt;
line-height:173%;font-family:宋体;mso-ascii-theme-font:minor-fareast;mso-fareast-theme-font:
minor-fareast;mso-hansi-theme-font:minor-fareast">拼接字符串

</h2>


[[File:135810boc06363pcocxhcn.png]]


<span lang="EN-US" style="font-size:12.0pt;font-family:宋体;
mso-ascii-theme-font:minor-fareast;mso-fareast-font-family:宋体;mso-fareast-theme-font:
minor-fareast;mso-hansi-theme-font:minor-fareast"><span style="mso-tab-count:
1">  <span style="font-size:12.0pt;font-family:宋体;mso-ascii-theme-font:
minor-fareast;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;
mso-hansi-theme-font:minor-fareast">通过该积木块，可将两个字符串拼接为一个字符串。


<h2><span lang="EN-US" style="font-size:12.0pt;line-height:173%;font-family:宋体;
mso-ascii-theme-font:minor-fareast;mso-fareast-theme-font:minor-fareast;
mso-hansi-theme-font:minor-fareast">2.4 <span style="font-size:12.0pt;
line-height:173%;font-family:宋体;mso-ascii-theme-font:minor-fareast;mso-fareast-theme-font:
minor-fareast;mso-hansi-theme-font:minor-fareast">字符串索引

</h2>


[[File:135810fj5j10asqq0bccws.png]]


<span lang="EN-US" style="font-size:12.0pt;font-family:宋体;
mso-ascii-theme-font:minor-fareast;mso-fareast-font-family:宋体;mso-fareast-theme-font:
minor-fareast;mso-hansi-theme-font:minor-fareast"><span style="mso-tab-count:
1">  <span style="font-size:12.0pt;font-family:宋体;mso-ascii-theme-font:
minor-fareast;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;
mso-hansi-theme-font:minor-fareast">通过该积木块，可通过字符串索引得到相应的字符，注意索引从0开始。


<h2><span lang="EN-US" style="font-size:12.0pt;line-height:173%;font-family:宋体;
mso-ascii-theme-font:minor-fareast;mso-fareast-theme-font:minor-fareast;
mso-hansi-theme-font:minor-fareast">2.5 <span style="font-size:12.0pt;
line-height:173%;font-family:宋体;mso-ascii-theme-font:minor-fareast;mso-fareast-theme-font:
minor-fareast;mso-hansi-theme-font:minor-fareast">字符串截取

</h2>


[[File:135810ffl2p4g0g44nrbb2.png]]


      <span style="font-size:12.0pt;
line-height:150%;font-family:宋体;mso-ascii-theme-font:minor-fareast;mso-fareast-font-family:
宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-theme-font:minor-fareast">通过该积木块，可截取给定字符串从给定索引开始，长度为给定长度的字符串。


<h2><span lang="EN-US" style="font-size:12.0pt;line-height:173%;font-family:宋体;
mso-ascii-theme-font:minor-fareast;mso-fareast-theme-font:minor-fareast;
mso-hansi-theme-font:minor-fareast">2.6 <span style="font-size:12.0pt;
line-height:173%;font-family:宋体;mso-ascii-theme-font:minor-fareast;mso-fareast-theme-font:
minor-fareast;mso-hansi-theme-font:minor-fareast">字符串比较

</h2>


[[File:135810puucsensscllssqn.png]]


<span lang="EN-US" style="font-size:
12.0pt;line-height:150%;font-family:宋体;mso-ascii-theme-font:minor-fareast;
mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-theme-font:
minor-fareast">  <span style="font-size:12.0pt;line-height:150%;font-family:宋体;mso-ascii-theme-font:
minor-fareast;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;
mso-hansi-theme-font:minor-fareast">通过该积木块，可将两字符串进行比较，两个字符串自左向右逐个字符相比（按ASCII值大小相比较），直到出现不同的字符或某一字符串比较完为止。设这两个字符串为str1，str2，若str1等于str2，则返回零；若str1小于str2，则返回负数；若str1大于str2，则返回正数。


<h2><span lang="EN-US" style="font-size:12.0pt;line-height:173%;font-family:宋体;
mso-ascii-theme-font:minor-fareast;mso-fareast-theme-font:minor-fareast;
mso-hansi-theme-font:minor-fareast">2.7 <span style="font-size:12.0pt;
line-height:173%;font-family:宋体;mso-ascii-theme-font:minor-fareast;mso-fareast-theme-font:
minor-fareast;mso-hansi-theme-font:minor-fareast">字符串转整数

</h2>


[[File:135810izuu2k3uu0kkn6j6.png]]


<span lang="EN-US" style="font-size:12.0pt;font-family:宋体;
mso-ascii-theme-font:minor-fareast;mso-fareast-font-family:宋体;mso-fareast-theme-font:
minor-fareast;mso-hansi-theme-font:minor-fareast"><span style="mso-tab-count:
1">  <span style="font-size:12.0pt;font-family:宋体;mso-ascii-theme-font:
minor-fareast;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;
mso-hansi-theme-font:minor-fareast">通过该积木块，可将数字字符串转换成整数。


<h1 style="line-height:150%"><span lang="EN-US" style="font-size:15.0pt;
line-height:150%;font-family:黑体;font-weight:normal;mso-bidi-font-weight:bold">3.<span style="font-size:15.0pt;line-height:150%;font-family:黑体;font-weight:normal;
mso-bidi-font-weight:bold">数学

</h1>

<span lang="EN-US" style="font-size:12.0pt;font-family:宋体;
mso-ascii-theme-font:minor-fareast;mso-fareast-font-family:宋体;mso-fareast-theme-font:
minor-fareast;mso-hansi-theme-font:minor-fareast"><span style="mso-tab-count:
1">  Micro:bit<span style="font-size:12.0pt;font-family:宋体;
mso-ascii-theme-font:minor-fareast;mso-fareast-font-family:宋体;mso-fareast-theme-font:
minor-fareast;mso-hansi-theme-font:minor-fareast">板载提供了若干数学运算：


<h2><span lang="EN-US" style="font-size:12.0pt;line-height:173%;font-family:宋体;
mso-ascii-theme-font:minor-fareast;mso-fareast-theme-font:minor-fareast;
mso-hansi-theme-font:minor-fareast">3.1<span style="font-size:12.0pt;
line-height:173%;font-family:宋体;mso-ascii-theme-font:minor-fareast;mso-fareast-theme-font:
minor-fareast;mso-hansi-theme-font:minor-fareast">四则运算

</h2>

      <span lang="EN-US" style="font-size:12.0pt;font-family:宋体;mso-ascii-theme-font:minor-fareast;
mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-theme-font:
minor-fareast">Micro:bit<span style="font-size:12.0pt;font-family:宋体;
mso-ascii-theme-font:minor-fareast;mso-fareast-font-family:宋体;mso-fareast-theme-font:
minor-fareast;mso-hansi-theme-font:minor-fareast">提供了四则运算积木块，有加减乘除运算，如下所示:




[[File:135811wef3z353q5y0fy5e.png]]


<span style="font-size:12.0pt;
line-height:150%;font-family:宋体;mso-ascii-theme-font:minor-fareast;mso-fareast-font-family:
宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-theme-font:minor-fareast">该积木块返回运算结果，是一个数字。



<span lang="EN-US" style="font-size:
12.0pt;line-height:150%;font-family:宋体;mso-ascii-theme-font:minor-fareast;
mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-theme-font:
minor-fareast">  <span style="font-size:12.0pt;line-height:150%;font-family:宋体;mso-ascii-theme-font:
minor-fareast;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;
mso-hansi-theme-font:minor-fareast">注意:四则运算不支持小数运算，并且，在除法中，将忽略余数。


<h2><span lang="EN-US" style="font-size:12.0pt;line-height:173%;font-family:宋体;
mso-ascii-theme-font:minor-fareast;mso-fareast-theme-font:minor-fareast;
mso-hansi-theme-font:minor-fareast">3.2<span style="font-size:12.0pt;
line-height:173%;font-family:宋体;mso-ascii-theme-font:minor-fareast;mso-fareast-theme-font:
minor-fareast;mso-hansi-theme-font:minor-fareast">产生随机数

</h2>

      随机选取从0到某个给定值范围内的随机数：




[[File:135811i3co2v004gcar2wc.png]]


  <span style="font-size:12.0pt;
font-family:宋体">随机选取true或false，作为判断条件：




[[File:135811e68sggsd4fh4m6mz.png]]

<h2><span lang="EN-US" style="font-size:12.0pt;line-height:173%;font-family:宋体;
mso-ascii-theme-font:minor-fareast;mso-fareast-theme-font:minor-fareast;
mso-hansi-theme-font:minor-fareast">3.3 <span style="font-size:12.0pt;
line-height:173%;font-family:宋体;mso-ascii-theme-font:minor-fareast;mso-fareast-theme-font:
minor-fareast;mso-hansi-theme-font:minor-fareast">取余数，最大值，最小值，绝对值

</h2>


[[File:135811nxrroceexegxr9ae.png]]

<h2><span lang="EN-US" style="font-size:12.0pt;line-height:173%;font-family:宋体;
mso-ascii-theme-font:minor-fareast;mso-fareast-theme-font:minor-fareast;
mso-hansi-theme-font:minor-fareast">3.4<span style="font-size:12.0pt;
line-height:173%;font-family:宋体;mso-ascii-theme-font:minor-fareast;mso-fareast-theme-font:
minor-fareast;mso-hansi-theme-font:minor-fareast">提取ASCII码

</h2>


[[File:135811r7zx2x6z27xj12xj.png]]


<span lang="EN-US" style="font-size:12.0pt;font-family:宋体;
mso-ascii-theme-font:minor-fareast;mso-fareast-font-family:宋体;mso-fareast-theme-font:
minor-fareast;mso-hansi-theme-font:minor-fareast"><span style="mso-tab-count:
1">  <span style="font-size:12.0pt;font-family:宋体;mso-ascii-theme-font:
minor-fareast;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;
mso-hansi-theme-font:minor-fareast">该积木块能够提取字符的ASCII码值，得到十进制数字。


<h1 style="line-height:150%"><span lang="EN-US" style="font-size:15.0pt;
line-height:150%;font-family:黑体;font-weight:normal;mso-bidi-font-weight:bold">4.<span style="font-size:15.0pt;line-height:150%;font-family:黑体;font-weight:normal;
mso-bidi-font-weight:bold">游戏

</h1>

      <span style="font-size:12.0pt;
line-height:150%;font-family:宋体">可基于Micro:bit屏幕(LED点阵)，结合按键，加速计，磁力计等，编写属于自己的游戏，并且:Micro:bit提供了方便编写游戏的相关积木块。