客户的需求是，输入半角字符或日语假名，筛选出来的结果显示包含该字符的半角形式和全角形式的所有结果，输入全角也是同样的结果。这里就需要将输入的字符全部转为半角和全角，再去匹配结果。
在网上搜了一圈之后，只找到了字符的全半角转换，日语的几乎没有，最后在GitHub到了自己想要的东西。
GitHub地址：https://github.com/shogo4405/KanaXS
字符的全半角转换如下：
全角转半角
function ToCDB(str) { ??????var tmp = ""; ??????for (var i = 0; i < str.length; i++) { ??????????if (str.charCodeAt(i) > 65248 && str.charCodeAt(i) < 65375) { ??????????????tmp += String.fromCharCode(str.charCodeAt(i) - 65248); ??????????} ??????????else { ??????????????tmp += String.fromCharCode(str.charCodeAt(i)); ??????????} ??????} ??????return tmp}半角转全角
function ToDBC(txtstring) { ???????var tmp = ""; ???????for (var i = 0; i < txtstring.length; i++) { ???????????if (txtstring.charCodeAt(i) == 32) { ???????????????tmp = tmp + String.fromCharCode(12288); ???????????} ???????????if (txtstring.charCodeAt(i) < 127) { ???????????????tmp = tmp + String.fromCharCode(txtstring.charCodeAt(i) + 65248); ???????????} ???????} ???if(isEmpty(tmp)){ ???????return txtstring; ???} ???return tmp;}全角转半角方法中，输入全角转换为半角，输入半角，返回的还是半角。
半角转全角方法中，输入半角转换为全角，输入全角，返回的是空，不利于后面的操作，所以如果转换后的结果是空，则返回输入的字符，实现了输入全角，返回的还是全角。
日语假名半角转全角
github上半角转全角的方法中，不包含小字符，如ぁ、ぃ、ぅ、ぇ、ぉ、っ、ゃ、ゅ、ょ，所以我在js文件中进行了改良，加入了这些小字符的Unicode码对照。完整代码如下：
/** * 半角のカタカナを全角のカタカナに変換します。 * @example * "?????".toZenkanaCase(); // アイウエオ * @return {String} */String.prototype.toZenkanaCase = function(){ ???var i, f, c, a = [], m = String.prototype.toZenkanaCase.MAPPING; ???for(i = 0, f = this.length;i < f; i++) ???{ ???????c = this.charCodeAt(i); ???????a.push(m[c] || c); ???}; ???return String.fromCharCode.apply(null, a);};String.prototype.toZenkanaCase.MAPPING = { ???????0xFF67:0x30A1, ???????0xFF68:0x30A3, ???????0xFF69:0x30A5, ???????0xFF6A:0x30A7, ???????0xFF6B:0x30A9, ???????0xFF70:0x30FC, ???????0xFF71:0x30A2, ???????0xFF72:0x30A4, ???????0xFF73:0x30A6, ???????0xFF74:0x30A8, ???????0xFF75:0x30AA, ???????0xFF76:0x30AB, ???????0xFF77:0x30AD, ???????0xFF78:0x30AF, ???????0xFF79:0x30B1, ???????0xFF7A:0x30B3, ???????0xFF7B:0x30B5, ???????0xFF7C:0x30B7, ???????0xFF7D:0x30B9, ???????0xFF7E:0x30BB, ???????0xFF7F:0x30BD, ???????0xFF80:0x30BF, ???????0xFF81:0x30C1, ???????0xFF82:0x30C4, ???????0xFF83:0x30C6, ???????0xFF84:0x30C8, ???????0xFF85:0x30CA, ???????0xFF86:0x30CB, ???????0xFF87:0x30CC, ???????0xFF88:0x30CD, ???????0xFF89:0x30CE, ???????0xFF8A:0x30CF, ???????0xFF8B:0x30D2, ???????0xFF8C:0x30D5, ???????0xFF8D:0x30D8, ???????0xFF8E:0x30DB, ???????0xFF8F:0x30DE, ???????0xFF90:0x30DF, ???????0xFF91:0x30E0, ???????0xFF92:0x30E1, ???????0xFF93:0x30E2, ???????0xFF94:0x30E4, ???????0xFF95:0x30E6, ???????0xFF96:0x30E8, ???????0xFF97:0x30E9, ???????0xFF98:0x30EA, ???????0xFF99:0x30EB, ???????0xFF9A:0x30EC, ???????0xFF9B:0x30ED, ???????0xFF9C:0x30EF, ???????0xFF9D:0x30F3, ???????0xFF9E:0x309B, ???????0xFF9F:0x309C, ???????0xFF66:0x30F2, ???????65383:12449, //ァ ???????65384:12451, //ィ ???????65385:12453, //ゥ ???????65386:12455, //ェ ???????65387:12457, //ォ ???????65391:12483, //ッ ???????65388:12515, //ャ ???????65389:12517, //ュ ???????65390:12519 ?//ョ};js 日文全半角转换
原文地址：https://www.cnblogs.com/ghq120/p/9573805.html