二维码是一种大多智能手机都能读取的二维平面条形码。使字符可读，即使某些部分丢失（但会使二维码更大）。级别1（L低）：可恢复7%的字符。二级（M中）：15%。三级（Q中高）：25%。四级（H高）：30%。在这里，您可以编码字母数字字符（0–9，A–Z，空格和$%*+-./：）或ISO-5589-1字符（意味着更多的字符，但它们占用了更多的空间）。理论上，EC level=1时，大小限制为4296（字母数字）或2953（ISO-5589-1）个字符，但如果使用超过500个字符，则方块会变得太小，并且很难读取。如果你想扫描读取二维码，你需要一部智能手机和某种扫描仪应用程序（有很多免费的）。 ------------------------------------------------------------------------- A QR code is a type of barcode that most smartphones can read. "EC level" (EC=error correction) allows to make the code readable even if some portion is lost (but it makes it bigger too). Level 1 (Low) : 7% of characters can be restored. Level 2 (Medium) : 15% of characters can be restored. Level 3 (Quartile) : 25% of characters can be restored. Level 4 (High) : 30% of characters can be restored. Here, you can encode alphanumeric characters (meaning: 0–9, A–Z, space and $%*+-./:) or ISO-5589-1 characters (meaning a whole lot more characters, but they take more room). In theory, the size limit is 4,296 (alphanumeric) or 2,953 (ISO-5589-1) characters with EC level=1, but if you use more than 500 characters, the squares get too small and it gets hard to read. If you want to read the QR code, you will need a smartphone (or a Nintendo DS) and some kind of scanner application (there are plenty for free, do a search for "QR code" on your application store).
改编版，新增鼠标滚轮介绍，需全屏 bug请指出
