js实现万级数字转汉字显示

const toChineseNum = (num) => {
  let dtext=['','十','百','千','万']
  let len=num.toString().length
  let numArr=num.toString().split('')
  let numTxt=''
  const toT=(numIndex)=>{
    const arr=['零','一','二','三','四','五','六','七','八','九']
    return arr[numIndex]
  }
  for(let i=1;i<=len;i++){
    if(len>5&&i<(len-3)){
      if(i==(len-4)){
          numTxt+=numArr[i-1]==0?'':toT(numArr[i-1])
          numTxt+='万'
      }else{
        if((numArr[i-2]==0&&numArr[i-1]==0)||((numArr[i-1]==0)&&(numArr[len-5]==0)&&numArr[i]==0)){
          numTxt+=''
        }else{
          numTxt+=(((numArr[i-1]==0)&&(numArr[len-5]!=0))||(numArr[i]!=0&&numArr[i-1]==0))?'零':(toT(numArr[i-1])+dtext[len-i-4])
      }
    }}else{
      if((numArr[i-1]==0&&i==len)||(numArr[i]==0&&numArr[i-1]==0)){
        numTxt+=''
      }else{
        numTxt+=numArr[i-1]==0?'零':(toT(numArr[i-1])+dtext[len-i])
      }
  }}
  return numTxt
}