C# 寻求较好的金额数字添加千分位分隔符的方法。

Question

功能是 能实现, 但是感觉不理想，因为就是对字符串的分割处理,设计的转换，拼接。寻求一个好的方法比如 Linq扩展方法 。把金额数字每三位加个符号。比如123456,123456789, 2345.456,要得到的结果是：123,456  ;  123,456,789  ;    2,345.456 ;实现方法如下：
/// <summary>
        /// 把数字转为要解析的字符串
        /// </summary>
        /// <param name="value"></param>
        /// <returns></returns>
        private string FormatValue(decimal value)
        {
            StringBuilder sb = new StringBuilder();
            string sValue = value.ToString();
            if (!IsHideZeroControl)//是否把不足位数补充0
            {
                if (sValue.Length < Length)
                {
                    int ids = Length - sValue.Length;
                    for (int i = 0; i < ids; i++)
                    {
                        sValue += "0";
                    }
                }
            }            if (IsShowSeparator )
            {
                List<string> list = new List<string>();                string temp = sValue;                bool includeFloat = sValue.LastIndexOf(".") != -1;                if (includeFloat)
                {
                    //temp = temp.Substring(0, sP);
                    temp = ((int)value).ToString();
                }
                int templength = temp.Length;
                if (temp.Length > 3)
                {
                    while (templength > 3)
                    {
                        list.Add(temp.Substring(templength - 3, 3));
                        templength -= 3;
                    }                    //最前面的添加进来
                    list.Add(temp.Substring(0, temp.Length - list.Count * 3));                    for (int i = list.Count - 1; i > 0; i--)
                    {
                        sb.Append(list[i] + ",");
                    }
                    sb.Append(list[0]);                    if (includeFloat)
                    {
                        sb.Append(sValue.Substring(sValue.LastIndexOf(".")));
                    }
                }
                else
                {
                    return sValue;
                }
            }
            return sb.ToString();
        }

Answer 1

忘记了把产品中的属性给去掉。 单独的方法应该是这样的；
/// <summary>
        /// 把数字转为要解析的字符串
        /// </summary>
        /// <param name="value"></param>
        /// <returns></returns>
        private string FormatValue(decimal value)
        {
            StringBuilder sb = new StringBuilder();            string sValue = value.ToString();            List<string> list = new List<string>();            string temp = sValue;            bool includeFloat = sValue.LastIndexOf(".") != -1;            if (includeFloat)
            {
                //temp = temp.Substring(0, sP);
                temp = ((int)value).ToString();
            }            int templength = temp.Length;            if (temp.Length > 3)
            {
                while (templength > 3)
                {
                    list.Add(temp.Substring(templength - 3, 3));
                    templength -= 3;
                }                //最前面的添加进来
                list.Add(temp.Substring(0, temp.Length - list.Count * 3));                for (int i = list.Count - 1; i > 0; i--)
                {
                    sb.Append(list[i] + ",");
                }
                sb.Append(list[0]);                if (includeFloat)
                {
                    sb.Append(sValue.Substring(sValue.LastIndexOf(".")));
                }
            }
            else
            {
                return sValue;
            }
            return sb.ToString();
        }

Answer 2

如果楼主只为显示数字的话，可以试试这个方法
double d = 1234567.123333;
Console.WriteLine(d.ToString("N2"));//N2中的2为保留2位小数，如果要保留三位可写为N3

Answer 3

 public string FormatValue(decimal value)
            {
                string tempStr = value.ToString();
                Match m = Regex.Match(tempStr,@"(\d+)(\.\d+)?");
                string before_str = m.Groups[1].Value;
                string after_str = m.Groups[2].Value;
                before_str = string.Join("",before_str.Reverse());
                before_str = Regex.Replace(before_str,@"(?<=\G\d{3})(?=(?!$).)",",");
                before_str = string.Join("", before_str.Reverse());
                return before_str+after_str;
            }不过就本国国情来讲，那么多小数貌似没什么意义

Answer 4

NumberFormatInfo应该可以解决你的问题。
数值类型的ToString方法有重载的带参的方法：
ToString()                      将此实例的数值转换为其等效的字符串表示形式。 （重写ValueType.ToString()。）
ToString(IFormatProvider)      使用指定的区域性特定格式信息，将此实例的数值转换为它的等效字符串表示形式。
ToString(String)              使用指定的格式，将此实例的数值转换为它的等效字符串表示形式。
ToString(String, IFormatProvider)   使用指定的格式和区域性特定格式信息，将此实例的数值转换为它的等效字符串表示形式。 

Answer 5

+1;这个还弄的这么纠结....string.Format()和tostring()都可以

Answer 6

private string FormatV(decimal value)
        {
            StringBuilder sb = new StringBuilder(string.Empty);            string sValue = value.ToString();            string temp = sValue;            bool includeFloat = sValue.LastIndexOf(".") != -1;            if (includeFloat)
            {
                //temp = temp.Substring(0, sP);
                temp = ((int)value).ToString();
            }            if (temp.Length > 3)
            {
                int len = sValue.Length;
                int leftnum = len % 3;                for (int i = 0; i < len; i++)
                {
                    sb.Append(sValue[i]);
                    if ((len - i - (leftnum - 1) - 1) % 3 == 0 && (len - i - (leftnum - 1) - 1) != 0)
                    {
                        sb.Append(',');
                    }
                }                if (includeFloat)
                {
                    sb.Append(sValue.Substring(sValue.LastIndexOf(".")));
                }
            }
            else
            {
                return sValue;
            }            return sb.ToString();
        }

Answer 7

这样写方便点，不过小数位数怎么办？ 不还是要截取小数点后面字符串 个数。
                 int n = sValue.Substring(sValue.LastIndexOf(".") + 1).Length;                string ccc = value.ToString("C" + n.ToString());

Answer 8

private string FormatValue(decimal value)
        {
            StringBuilder sb = new StringBuilder(string.Empty);            string sValue = value.ToString();            string temp = sValue;            var sdf = sValue.Split('.');            if (sdf.Length > 1)
            {
                temp = sdf[0];
            }            if (temp.Length > 3)
            {
                int len = temp.Length;
                int startPosition = 4;                for (int i = 0; i < len; i++)
                {
                    sb.Append(temp[i]);                    int n = len - i;
                    int condition = n - startPosition;                    if (condition % 3 == 0 && condition >= 0)
                    {
                        sb.Append(',');
                    }
                }                if (sdf.Length > 1)
                {
                    sb.Append('.').Append(sdf[1]);
                }
            }
            else
            {
                return sValue;
            }            return sb.ToString();
        }

Answer 9

private string FormatV(decimal value)
        {
            StringBuilder sb = new StringBuilder(string.Empty);            string sValue = value.ToString();            string temp = sValue;            var sdf = sValue.Split('.');            if (sdf.Length > 1)
            {
                temp = sdf[0];
            }            if (temp.Length > 3)
            {
                int len = temp.Length;                int startPosition = len % 3 == 0 ? 2 : len % 3 - 1;                int j = 0;                for (int i = 0; i < len; i++)
                {
                    sb.Append(temp[i]);                    if (i == (startPosition + j * 3) && i != len - 1)
                    {
                        sb.Append(',');
                        j++;
                    }
                }                if (sdf.Length > 1)
                {
                    sb.Append('.').Append(sdf[1]);
                }
            }
            else
            {
                return sValue;
            }            return sb.ToString();
        }改成这样好理解点，而且似乎更好一些

Answer 10

簡單的功能不需要用太多複雜的手段...
下面是我的做法,而且不受位數影響^_^private string formatThousnadSymaol(string SrcNum)
{
    string flt = SrcNum.IndexOf('.') < 0 ? "" : SrcNum.Split('.')[1];
    SrcNum = SrcNum.Split('.')[0];
    int pnt = SrcNum.Length % 3;
    if (SrcNum.Length > 3)
    {
        while (pnt + 1 < SrcNum.Length)
        {
            int i = pnt % 4 == 0 ? pnt : pnt + 1;
            if (i > 0) SrcNum = SrcNum.Insert(i - 1, ",");
            pnt += 4;
        }
    }
    return SrcNum + flt;
}