如何控制小数位数

Question

datagridview中绑定一个查询结果，类似如下语句
select 价格，数量，价格*数量 as 金额 from table
其中，价格是6位小数，数量是整数，
现在，金额显示的是6位小数
我想在datagridview中，实现金额是两位的显示效果，如何做呀？
控制sql语句，或datagridview显示效果都行。

Answer 1

public class FormatSpecApp
{
    public static void Main(string[] args)
    {
        int i = 123456;
        Console.WriteLine("{0:C}", i); // ￥123,456.00
        Console.WriteLine("{0:D}", i); // 123456
        Console.WriteLine("{0:E}", i); // 1.234560E+005
        Console.WriteLine("{0:F}", i); // 123456.00
        Console.WriteLine("{0:G}", i); // 123456
        Console.WriteLine("{0:N}", i); // 123,456.00
        Console.WriteLine("{0:P}", i); // 12,345,600.00 %
        Console.WriteLine("{0:X}", i); // 1E240
    }
}

Answer 2

            double i = 123456.42;
            Console.WriteLine();
            Console.WriteLine("{0:000000.00}", i); //123456.42
            Console.WriteLine("{0:00.00000000e+0}", i); //12.34564200e+4
            Console.WriteLine("{0:0,.}", i);          //123
            Console.WriteLine("{0:#0.000}", i);             // 123456.420
            Console.WriteLine("{0:#0.000;(#0.000)}", i);        // 123456.420
            Console.WriteLine("{0:#0.000;(#0.000);<zero>}", i); // 123456.420
            Console.WriteLine("{0:#%}", i);     // 12345642%            i = -123456.42;
            Console.WriteLine();
            Console.WriteLine("{0:000000.00}", i); //-123456.42
            Console.WriteLine("{0:00.00000000e+0}", i); //-12.34564200e+4
            Console.WriteLine("{0:0,.}", i);          //-123
            Console.WriteLine("{0:#0.000}", i);             // -123456.420
            Console.WriteLine("{0:#0.000;(#0.000)}", i);        // (123456.420)
            Console.WriteLine("{0:#0;(#0);<zero>}", i); // (123456)
            Console.WriteLine("{0:#%}", i);             // -12345642%            i = 0;
            Console.WriteLine();
            Console.WriteLine("{0:0,.}", i);          //0
            Console.WriteLine("{0:#0}", i);             // 0
            Console.WriteLine("{0:#0;(#0)}", i);        // 0
            Console.WriteLine("{0:#0;(#0);<zero>}", i); // <zero>
            Console.WriteLine("{0:#%}", i);             // %

Answer 3

用datagridview控制比较好！
还需要四舍五入吗？

Answer 4

Math.Round(number,2);number.ToString("F2");

Answer 5

select  价格，数量，convert(numeric(12,2),round(价格*数量,2)) as 金额 from table   

Answer 6

stringstr1 =string.Format("{0:N1}",56789);               //result: 56,789.0
stringstr2 =string.Format("{0:N2}",56789);               //result: 56,789.00
stringstr3 =string.Format("{0:N3}",56789);               //result: 56,789.000
stringstr8 =string.Format("{0:F1}",56789);               //result: 56789.0
stringstr9 =string.Format("{0:F2}",56789);               //result: 56789.00
stringstr11 =(56789 / 100.0).ToString("#.##");           //result: 567.89
stringstr12 =(56789 / 100).ToString("#.##");             //result: 567

Answer 7

F 或 f
固定点
Console.Write("{0:F2}", 25);  //25.00
Console.Write("{0:F0}", 25);  //25

Answer 8

就是这个了,直接在sql里面处理来得快

Answer 9

我是用            dataGridView1.DataSource = dt;
绑定的，
math函数 或 Console.WriteLine("{0:C}",  怎么用呀？是不是要一行一行重写datagridview呀？

Answer 10

 this.dataGridView1.Columns[X].DefaultCellStyle.Format = "0.00";//X是你那一列所在的索引

Answer 11

        
double a = Math.Round(123.123456, 2);// ,2 代表位数
//a 结果是123.12
//先读出来金额，然后用 Math.Round 控制只显示2位小数
//然后在赋给datagridview

Answer 12

select  价格，数量，convert(numeric(12,2),round(价格*数量,2)) as 金额 from table 
这个吧.
查出来就是带小数的了.

Answer 13

select 价格，数量，round(价格*数量,2) as 金额 from table 

Answer 14

select  价格，数量，convert(numeric(12,2),round(价格*数量,2)) as 金额 from table 
应该可以

Answer 15

可以直接在dataGridView1,绑定列里面 用这个参数保留2位 format(...,"0.00")

Answer 16

select convert(numeric(12,2),价格*数量) as 金额 from table