使用自定义舍入和千位分隔符打印双精度

Question

I've a lot of number to format and I would like them to be readable easily but my users. I need to have:

• Custom rounding values (from 0 to 10)
• Thousand Separator
• Less garbage
• fast processing (update rate : ~10hz)

The best I came up with is this code:

private string RoundToString(double d)
{
    return Double.IsNaN(d) ? "Out Of Bounds" : d.ToString("N" + (int)numUpDownRoundValue.Value);
}

but I get a lot of useless 0 if the rounding is high:

182,0000000000  370,5000000000          370,5444319880  121,0000000000  517,0000000000  5 949 090,8555680300                        
105,3700000000  158,2750000000          165,4869516069  74,1850000000   245,4200000000  2 656 893,0080484100            
107 277,0000000000  109 452,0000000000          110 879,4795092180  100 261,0000000000  119 221,0000000000  1 780 170 043,5204900000

I also try this one:

private string RoundToString(double d)
{
    return Double.IsNaN(d) ? "Out Of Bounds" : Math.Round(d, (int)numUpDownRoundValue.Value).ToString("N");
}

But the N option crop to early (loss of precision)

Edit

What I want :

182 370,5 -- 370,5444319880 -- 121 517 -- 5 949 090,85556803                    
105,37 -- 158,275 -- 165,4869516069 -- 74,185 -- 245,42 -- 2 656 893,00804841           
107 277 -- 109 452 -- 110 879,479509218 -- 100 261  119 221 -- 1 780 170 043,52049

In other words, I want thousand separator and no useless zeros.

Answer 1

如果您希望小数点后最多 10位，但又不想训练零，请使用：

d.ToString("#,##0."+new string('#',(int)numUpDownRoundValue.Value))

Answer 2

What about:

d.ToString("#,#.##########")

Look up custom numeric format on the msdn site.