截取小数点后几位的方法

 /// <summary>
    /// 用来截取小数点后nleng位
    /// </summary>
    /// <param name="sString">sString原字符串。</param>
    /// <param name="nLeng">nLeng长度。</param>
    /// <returns>处理后的字符串。</returns>
    public string VarStr(string sString, int nLeng)
    {
        int index = sString.IndexOf(".");
        if (index == -1 || index + nLeng >= sString.Length)
            return sString;
        else
            return sString.Substring(0, (index + nLeng + 1));
    }