c# - Ternary Best Practice

Question

I have a bit of code, that while simple perhaps isn't immediately obvious as to what it does.

I found @(Model.Count() == 0 ? "no" : Model.Count().ToString()) @(Model.Count() == 1 ? "person" : "people")
@foreach (var item in Model) {
   <div>@item.Name at @item.Email</div>
}

And before I write lots of code like this, I wanted to know if this is a good way of doing this.

Thus the question is, in .NET is there a better framework way of doing this, or is the Ternary method fine

The premise is obviously

0 records = I found no people
1 record = I found 1 person
2+ records = I found 2 people

score 5 · Accepted Answer

如果您在几个地方这样做，扩展方法将解决您的两个问题（可读性和简化代码）

public static string PersonCountString(this IEnumerable<Person> personList)
{
    var count = personList.Count();
    return String.Format("{0} {1}", count > 0 ? count : "no",
                                    count == 1 ? "person" : "people");
}
...
I found (@Model.PersonCountString())

score 5 · Accepted Answer

在我看来，在Ternary这种情况下使用条件运算符绝对没问题。

有经验的开发者不假思索地理解它，但如果你想让它易于初学者阅读，你也可以使用ifandelse构造。

但我会使用Any()评论中提到的@I4V。

I found @(Model.Any() ? Model.Count().ToString() : "no") @(Model.Count() == 1 ? "person" : "people")


@foreach (var item in Model) {
   <div>@item.Name at @item.Email</div>
}

score 1 · Accepted Answer

回答你的问题：不，我发现 oneliner 不可读，它读起来像@(() 0 ? "" : .().()) @(.() == 1 ? "" : "")我，更不用说多次调用.Count().

您可以像这样创建一个（共享的）辅助方法：

string GetCountWithDescription(int count, 
                               string singleItemDescription, 
                               string multipleItemsDescription)
{
    switch (count)
    {
        case 0:
            return "no " + multipleItemsDescription;
        case 1:
            return "1 " + singleItemDescription;
        default:            
            return count + " " + multipleItemsDescription;
    }
}

也可以重用，所以你可以把它放在一个单独的文件中，这样它就不会弄乱你的代码，你可以简单地从每个视图中调用它，如下所示：

@GetCountWithDescription(Model.Count(), "person", "people")

score 0 · Accepted Answer

你想达到什么目标？更好的可读性或更快的代码（开发）？如果目的是提高可读性，那么我建议将三元运算保留在字符串中，例如：

string modelCountStr = Model.Count() == 0 ? "no" : Model.Count().ToString(); string modelPluralStr = Model.Count() == 1 ? "person" : "people";

score 0 · Accepted Answer

Count()考虑到如果有任何用户存在，您将不得不使用：

@{ 
    var count = Model.Count();
}

I found @(count == 0 ? "no" : count) @(count == 1 ? " person" : " people")

score 0 · Accepted Answer

使其更具可读性的另一种方法是选择一个解决方案，如果可能的话，涉及的条件尽可能少或理想情况为零。

这是我的看法：

@{ 
    var count = Model.Count(); 
}
I found @string.Format(new[] { "no people", "{0} person", "{0} people"} [Math.Min(count, 2)], count)

可以说 Math.Min 负责某种分支，但我认为这更容易理解。

c# - Ternary Best Practice

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