C# 四捨五入 進一法 直接取整 帶小數位元

[一籃飯特稀原創，轉載請註明出處http://www.cnblogs.com/wanghafan/archive/2012/05/18/2508113.html]

四捨五入

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1         public static decimal Round(decimal d, decimal unit)2         {3             decimal rm = d % unit;4             decimal result = d - rm;5             if (rm >= unit / 2)6                 result += unit;7             return result;8         }

 

進一法

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1         public static decimal Jinyi(decimal d, decimal unit)2         {3             decimal rm = d % unit;4             decimal result = d - rm;5             if (rm > 0)6                 result += unit;7             return result;8         }

 

直接取整

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1         public static decimal Quzheng(decimal d, decimal unit)2         {3             decimal rm = d % unit;4             decimal result = d - rm;5             return result;6         }

 

 

 

調用方式

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 1 int cou = 3; 2 string uit = string.Empty; 3 int cou = int.Parse(dt.Rows[0]["小數位元"].ToString()); 4 if (cou == 0) 5 { 6     uit = "1"; 7 } 8 else 9 {10     uit = "0.";11     for (int i = 1; i < cou; i++) 12     uit += "0";13     uit += "1";14 }15  16 Jinyi(num, decimal.Parse(uit));17 Round(num, decimal.Parse(uit));18 Quzheng(num, decimal.Parse(uit));