JS 英文數字全形轉半形

const FullShapeToHalfShape　= (str) => {
  return str.replace(/[\uff01-\uff5e]/g, function (ch) {
    return String.fromCharCode(ch.charCodeAt(0) - 0xfee0)
  }).replace(/\u3000/g, ' ')
}


var inputStr = 'ＡＢＣＤＥＦＧ１２３'

console.log(FullShapeToHalfShape(inputStr))

// 輸出：abcdefg123