不能做除法 [英] Can't do division

问题描述

int h1 = 2;
int d1 = 4;
decimal c1 = d1/(d1+h1);
Console.WriteLine("{0:F9}", c1);

控制台显示0,00000000000，但我期望看到0,6666666并在年底，也许7。有什么问题？我尝试了不同的方法，但总能看到0,00000000 ...

Console shows 0,00000000000, but I expected to see 0,6666666 and maybe 7 in the end. What's the problem? I tried different methods, but always see 0,00000000...

推荐答案

这是因为你做的整数除法。你需要投一个值，以做一个小数除法为十进制：

It's because you're doing an integer division. You need to cast one value to decimal in order to do a decimal division :

int h1 = 2;
int d1 = 4;
decimal c1 = (decimal)d1 / (d1 + h1);

基本上，你可以翻译当前存在问题的行为：

Basically, you can translate the current problematic behavior as:

decimal c1 = (decimal)(d1 / (d1 + h1));
decimal c1 = (decimal)(4 / (2 + 4));
decimal c1 = (decimal)(4 / 6);
decimal c1 = (decimal)(0); <-- Integer division
decimal c1 = 0m;

这就是为什么你需要或者分子或分母是明确一个小数了。

That's why you need either the numerator or denominator to be explicitly a decimal already.

此外，在这里你的铸造是完全不相干的，你只需要触发小数除法。这4条线具有完全相同的结果：

Also, where you do the casting it is totally irrelevant, you just need to trigger the decimal division. Those 4 lines have exactly the same result :

decimal c1 = (decimal)d1 / (d1 + h1);
decimal c2 = d1 / ((decimal)d1 + h1);
decimal c3 = d1 / (d1 + (decimal)h1);
decimal c4 = d1 / (decimal)(d1 + h1);

这篇关于不能做除法的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！