商品金额格式转化

代码如下：

// 价格过滤
//  例：3400      3,400
function toThousands(nStr: string) {
  nStr += ""
  const x = nStr.split(".")
  let x1 = x[0]
  const x2 = x.length > 1 ? "." + x[1] : ""
  const rgx = /(\d+)(\d{3})/
  while (rgx.test(x1)) {
    x1 = x1.replace(rgx, "$1" + "," + "$2")
  }
  return x1 + x2
}