JavaScript 正則表達式去除數字逗號數字中的逗號

Question

"12,56,7abc,fgh" ===> "12567abc,fgh"
"1,245abc,1a" ===> "1245abc,1a"
"1,2,3,4,5abc" ===> "12345abc"

如何刪除(number),(number)格式的逗號？

對於測試

const array = ["12,56,7abc,fgh", "1,245abc,1a", "1,2,3,4,5abc"]
const answer = ["12567abc,fgh", "1245abc,1a", "12345abc"]

function formatter(string){
   // here
   return // string.replace('', '') ??
}

array.map((el, i) => { 
   const formatted = formatter(el) 
   if(answer[i] === formatted){
      console.log('Success. formatted: ', formatted)
   } else {
     console.log('Failed. formatted: ', formatted)
   }
})

Answer 1

str.replace(/(?<=\d),(?=\d)/g, '')

(?<=\d): 向后看 - 一個數字

(?=\d): 前瞻 - 一個數字