blocks|key|61657|text|我不认为这样做有什么意义，因为您正在添加额外的代码，而这些代码实际上什么也不做。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|61658|如果您试图默认(类)，也会得到null。|61659|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|F|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|G|8|@]|9|@]|A|$]]|$1|D|3|-4|5|6|7|H|8|@]|9|@]|A|$]]]|E|$]]

I don't really see a point in doing so, since you're adding extra code that really does nothing.

Same would apply if you were trying to default(class), you'd get null.

blocks|key|61679|text|private+int+_myInt+=+int.MinValue;和default(int)是不同的。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|61680|这完全取决于你的要求。如果您希望您的变量有一个值，那么IMO使用default将更加可读性和清晰度。|61681|它只对函数局部变量重要，对于类字段，它将由编译器完成。|61682|entityMap^0|0|Y|Z|C|0|W|7|0|0^^$0|@$1|2|3|4|5|6|7|L|8|@$9|M|A|N|B|C]|$9|O|A|P|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|Q|8|@$9|R|A|S|B|C]]|D|@]|E|$]]|$1|H|3|I|5|6|7|T|8|@]|D|@]|E|$]]|$1|J|3|-4|5|6|7|U|8|@]|D|@]|E|$]]]|K|$]]

<code>private int _myInt = int.MinValue;</code> and <code>default(int)</code> are different. 

It all depends on your requirement. If you want your variables to have a value then IMO using <code>default</code> is more readable and clear. 

It only matters to variables local to your function, for class fields it would be done by the compiler.

blocks|key|1173036|text|将字段初始化为default(T)没有价值，因为这是由编译器“默认”完成的。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1173037|如果在使用变量之前总是设置变量，那么初始化任何变量的值就更少了：|1173038|public+void+Foo(){
++++DataSet+ds+=+null;
++++ds+=+new+DataSet();
}|code-block|syntax|javascript|1173039|为什么要在设置之前把它清除掉呢？|1173040|entityMap^0|7|A|0|0|0|0^^$0|@$1|2|3|4|5|6|7|Q|8|@$9|R|A|S|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|T|8|@]|D|@]|E|$]]|$1|H|3|I|5|J|7|U|8|@]|D|@]|E|$K|L]]|$1|M|3|N|5|6|7|V|8|@]|D|@]|E|$]]|$1|O|3|-4|5|6|7|W|8|@]|D|@]|E|$]]]|P|$]]

There is no value in initializing fields to <code>default(T)</code>, since that is done by the compiler "by default".

There is even less value in initializing any variable if that variable will always be set before it is used:

<pre><code>public void Foo(){
 DataSet ds = null;
 ds = new DataSet();
}
</code></pre>

Why clear it before you set it?

blocks|key|67095|text|添加命令编译器做它无论如何都要做的事情的语句是一种糟糕的做法(这也适用于bool+_myBool+=+false，尽管程度较小)。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|67096|与必须显式分配的局部变量不同，字段被隐式初始化为其默认值。编译器已经知道要这样做了，所以额外的代码绝对不是针对编译器的。|67097|由于您的代码的唯一其他“使用者”是您的读取器，所以问题归结为“期望读者知道类中的字段被初始化为默认值是合理的吗？”我认为答案应该是“是”，因为这是极其基本的知识。|67098|entityMap^0|10|K|0|0|0^^$0|@$1|2|3|4|5|6|7|L|8|@$9|M|A|N|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|O|8|@]|D|@]|E|$]]|$1|H|3|I|5|6|7|P|8|@]|D|@]|E|$]]|$1|J|3|-4|5|6|7|Q|8|@]|D|@]|E|$]]]|K|$]]

Adding statements directing the compiler to do what it is going to do anyway is a bad practice (that applies to <code>bool _myBool = false</code> as well, albeit to a lesser degree).

Unlike locals that must be assigned explicitly, fields are implicitly initialized to their defaults. The compiler already knows to do that, so the additional code is definitely not for the compiler.

Since the only other "consumers" of your code are your readers, the question boils down to "is is reasonable to expect a reader to know that fields in a class are initialized to their default values?" I think the answer should be "yes", because this is extremely basic knowledge.

blocks|key|1172475|text|从某种意义上说，它增加了代码读者的认知负担，这是许多人认为是有害的做法。如果我看到初始化，我希望它能提供一些真正的意义。default关键字的主要用法是泛型。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1172476|entityMap^0|1O|7|0^^$0|@$1|2|3|4|5|6|7|H|8|@$9|I|A|J|B|C]]|D|@]|E|$]]|$1|F|3|-4|5|6|7|K|8|@]|D|@]|E|$]]]|G|$]]

In the sense that it increases the cognitive load on readers of your code, this is a practice many would view as being detrimental. If I see an initialization, I expect it to provide some real meaning. The main use of the <code>default</code> keyword is with generics.

Historically speaking, I have initialized member variables prior to assignment like so:

<pre><code>private bool _myBool = false;
private int _myInt = int.MinValue;
private string _myString = String.Empty;
</code></pre>

Lately I've found myself initializing them like so (normally with primitives):

<pre><code>private DateTime _myDateTime = default(DateTime);
private bool _myBool = default(bool);
//etc
</code></pre>

Is this a bad or good practice? How come?

Is it a bad idea to use the default keyword when initializing member variables?

翻译质量差，导致语言生硬或混乱。

没有提供实际的解决方法或示例。

解答不清晰，无法理解或解决问题。

页面排版不美观，阅读体验差。

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从历史上讲，我在分配之前初始化了成员变量，如下所示：private bool _myBool = false;private int _myInt = int.MinValue;private string _myString = String.Empty;最近，我发现自己是这样初始化它们的(通常使用原语)：priva...

问初始化成员变量时使用默认关键字是个坏主意吗？
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问初始化成员变量时使用默认关键字是个坏主意吗？EN