主要用到 str.charCodeAt()和 String.fromCharCode()方法
–》使用 charCodeAt() 来获得字符串中某个具体字符的 Unicode 编码。
–》fromCharCode() 可接受一个（或多个）指定的 Unicode 值，然后返回对应的字符串。
//生成大写字母 A的Unicode值为65function generateBig_1(){var str = [];for(var i=65;i<91;i++){str.push(String.fromCharCode(i));}return str;}//生成大写字母 a的Unicode值为97function generateSmall_1(){var str = [];for(var i=97;i<123;i++){str.push(String.fromCharCode(i));}return str;}//将字符串转换成Unicode码function toUnicode(str){var codes = [];for(var i=0;i<str.length;i++){codes.push(str.charCodeAt(i));}return codes;}function generateSmall(){var ch_small = 'a';var str_small = '';for(var i=0;i<26;i++){str_small += String.fromCharCode(ch_small.charCodeAt(0)+i);}return str_small;}function generateBig(){var ch_big = 'A';var str_big = '';for(var i=0;i<26;i++){str_big += String.fromCharCode(ch_big.charCodeAt(0)+i);}return str_big;}console.log(generateBig());console.log(generateSmall());console.log(toUnicode(generateBig()));console.log(toUnicode(generateSmall()));console.log(generateBig_1());console.log(generateSmall_1());
