swift 整数不显示小数点，小数点最多显示后两位

 

    ///字符串转双精度后去除小数点00
    static func convertStringToString(_ str: String) -> String? {
        if let doubleValue = Double(str) {
            let numberFormatter = NumberFormatter()
            numberFormatter.minimumFractionDigits = 0
            numberFormatter.maximumFractionDigits = doubleValue.truncatingRemainder(dividingBy: 1) == 0 ? 0 : 2
            return numberFormatter.string(from: NSNumber(value: doubleValue))
        }
        return nil
    }