blocks|key|1371820|text|DefaultValue属性仅用于告诉Visual+Studio设计器(例如，在设计窗体时)属性的默认值是什么。它不会在代码中设置属性的实际默认值。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1371821|更多信息请点击此处：http://support.microsoft.com/kb/311339|offset|length|1371822|entityMap|0|LINK|mutability|MUTABLE|url|http://support.microsoft.com/kb/311339^0|0|A|12|0|0^^$0|@$1|2|3|4|5|6|7|N|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|O|8|@]|9|@$D|P|E|Q|1|R]]|A|$]]|$1|F|3|-4|5|6|7|S|8|@]|9|@]|A|$]]]|G|$H|$5|I|J|K|A|$L|M]]]]

The DefaultValue attribute is only used to tell the Visual Studio Designers (for example when designing a form) what the default value of a property is. It doesn't set the actual default value of the attribute in code.

More info here: <a href="http://support.microsoft.com/kb/311339" rel="noreferrer">http://support.microsoft.com/kb/311339</a>

blocks|key|1371876|text|[DefaultValue]仅由(例如)序列化API(如XmlSerializer)和一些UI元素(如PropertyGrid)使用。它不设置值本身；您必须使用构造函数来设置值：|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1371877|public+MyType()
{
++++RetrieveAllInfo+=+true;
}|code-block|syntax|javascript|1371878|或者手动设置字段，即不使用自动实现的属性：|1371879|private+bool+retrieveAllInfo+=+true;
[DefaultValue(true)]
public+bool+RetrieveAllInfo+{
++++get+{return+retrieveAllInfo;+}
++++set+{retrieveAllInfo+=+value;+}
}|1371880|1371881|或者，使用更新的C#版本(C#+6或更高版本)：|1371882|[DefaultValue(true)]
public+bool+RetrieveAllInfo+{+get;+set;+}+=+true;|1371883|entityMap^0|0|E|S|D|1F|C|0|0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|V|8|@$9|W|A|X|B|C]|$9|Y|A|Z|B|C]|$9|10|A|11|B|C]]|D|@]|E|$]]|$1|F|3|G|5|H|7|12|8|@]|D|@]|E|$I|J]]|$1|K|3|L|5|6|7|13|8|@]|D|@]|E|$]]|$1|M|3|N|5|H|7|14|8|@]|D|@]|E|$I|J]]|$1|O|3|-4|5|6|7|15|8|@]|D|@]|E|$]]|$1|P|3|Q|5|6|7|16|8|@]|D|@]|E|$]]|$1|R|3|S|5|H|7|17|8|@]|D|@]|E|$I|J]]|$1|T|3|-4|5|6|7|18|8|@]|D|@]|E|$]]]|U|$]]

<code>[DefaultValue]</code> is only used by (for example) serialization APIs (like <code>XmlSerializer</code>), and some UI elements (like <code>PropertyGrid</code>). It doesn't set the value itself; you must use a constructor for that:
<pre><code>public MyType()
{
 RetrieveAllInfo = true;
}
</code></pre>
or set the field manually, i.e. not using an automatically implemented-property:
<pre><code>private bool retrieveAllInfo = true;
[DefaultValue(true)]
public bool RetrieveAllInfo {
 get {return retrieveAllInfo; }
 set {retrieveAllInfo = value; }
}
</code></pre>
<hr />
Or, with more recent C# versions (C# 6 or above):
<pre class="lang-cs prettyprint-override"><code>[DefaultValue(true)]
public bool RetrieveAllInfo { get; set; } = true;
</code></pre>

blocks|key|1371946|text|针对这一点的一种攻击是在this链接上。|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|1371947|简而言之，在构造函数的末尾调用此函数。|1371948|static+public+void+ApplyDefaultValues(object+self)
+++{
++++++++foreach+(PropertyDescriptor+prop+in+TypeDescriptor.GetProperties(self))+{
++++++++++++DefaultValueAttribute+attr+=+prop.Attributes[typeof(DefaultValueAttribute)]+as+DefaultValueAttribute;
++++++++++++if+(attr+==+null)+continue;
++++++++++++prop.SetValue(self,+attr.Value);
++++++++}
+++}|code-block|syntax|javascript|1371949|entityMap|0|LINK|mutability|MUTABLE|url|http://www.barsoom.org/defaultvalue-attribute-initial^0|C|4|0|0|0|0^^$0|@$1|2|3|4|5|6|7|S|8|@]|9|@$A|T|B|U|1|V]]|C|$]]|$1|D|3|E|5|6|7|W|8|@]|9|@]|C|$]]|$1|F|3|G|5|H|7|X|8|@]|9|@]|C|$I|J]]|$1|K|3|-4|5|6|7|Y|8|@]|9|@]|C|$]]]|L|$M|$5|N|O|P|C|$Q|R]]]]

One hack for this is on <a href="http://www.barsoom.org/defaultvalue-attribute-initial" rel="nofollow">this</a> link.

In short, call this function at the end of constructor. 

<pre><code>static public void ApplyDefaultValues(object self)
 {
 foreach (PropertyDescriptor prop in TypeDescriptor.GetProperties(self)) {
 DefaultValueAttribute attr = prop.Attributes[typeof(DefaultValueAttribute)] as DefaultValueAttribute;
 if (attr == null) continue;
 prop.SetValue(self, attr.Value);
 }
 }
</code></pre>

I have the following Auto Property 

<pre><code>[DefaultValue(true)]
public bool RetrieveAllInfo { get; set; }
</code></pre>

when I try to use it inside the code i find the default false for is <code>false</code> I assume this is the default value to a <code>bool</code> variable, does anyone have a clue what is wrong!?

DefaultValue attribute is not working with my Auto Property

Visual Studio

我有以下Auto属性[DefaultValue(true)]public bool RetrieveAllInfo { get; set; }当我试图在代码中使用它时，我发现false的缺省值为false，我假设这是bool变量的缺省值，有人知道出了什么问题吗？

问DefaultValue属性不适用于我的自动属性
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